My dilemma is whether I should continue this campaign with my current party, disband it entirely and get a new party, or get rid of the ones I don't like and replace them with others. I really don't want to throw away this world I love and have some bad players waste it. Here's the rundown from my point of view. 

I have made a campaign that I absolutely LOVE, and I invited some friends to play. It started with Lost Mine of Phandelver but I ended up making an entirely new world when they finished the first goblin cave. Before I made it my own, I had two players leave. After, I invited a friend of mine. We played three sessions with a group of three, then I invited another person. Four players for a session. Then another joined. Five. Now, I like four of the characters, but only two players are good. One is afraid of being op so he nerfed himself(he's the Barbarian. My Blood Hunter does more damage in a round than him.), he hates homebrew(I love it and so do the others), DMs for me(when the players have a question he answers it and he acts like the DM when he does), and gets on my nerves often. The other is still shy of rping and is also new. We're about 10 sessions in and nothing has changed. She also has the worst attendance. The fifth one never shows up and doesn't rp well.
The two I like rp well, are creative and are really into this campaign. The Barb is into it as well, but he can be really annoying most times for me and the Blood Hunter.

I have a game tonight and I think I will run this game and decide. Your opinion will help lots though.

Thank you if you responded. If not, thank you for reading my rant.

If you want to save your sanity, I would advise keeping the people you like and booting the others. Let them know why they are being booted, do not be shy. The Backseat DM needs to go, no room for your vision of the game to be interrupted by someone else. Get rid of the MIA player, no need to design encounters and have it be a waste of time when one person misses out, a real pain in the balls to readjust everything due to an MIA player. If a player annoys you get rid of him, there are a crap ton more players to choose from out there.Basically you do not have to be tethered to players you do not like, or drive you nuts.

Normally a good Session 0 would iron a lot of this out.  By continuing the campaign and adding and dropping players, some things seem to have crept in.  Sounds like you need to have a Mid-Season Session 0.  Or rather, it looks like you need to talk to two players before having a Session 0 in the middle.  Ask the problematic guy if he is actually enjoying the table... it seems that he doesn't like the same things that nearly everyone else does.  Give him a flat warning on trying to be the DM at the table, that he has used up his privilege of answering questions.  I mean, you can be polite about it or ask him what is it about trying to second-chair DM you that makes him keep wanting to do it. Regardless, let him know that is the main thing that is getting on your nerves and making the game un-fun for you as well.  

The Shy Roleplayer.  Ask them what is fun about the game.  Find out if she knows enough about her character to even begin to roleplay.  Too many people have a basic framework for what their character can do, but have no idea of what that character likes, what their childhood was like, what attitude they walk around with every day.  Ask what would be a fun scene for her to take her character into.  Maybe a salon day, maybe a personal session with a trainer, maybe a museum, maybe a walk on the beach with someone that she admires.  Some really good roleplayers are shy, but if given the opportunity to blossom they can come out of their shell.  They typically aren't going to do that in the midst of rapid fire banter or in combat.  Some of the same things might be applicable to the missing person, but odds are something at the table is making them uncomfortable.  Find out and see if you can correct it.

Good luck... all tables have some rocky patches.  Good communications and open expectations can go a long way toward making everyone come together and make the experience better.  Sometimes, someone isn't meant for the table and if everyone honestly tries and it just isn't working out, they can see you tried.  Even if you have to tell them that "Thanks, but no thanks."

Thank you! This helped a ton. 

Quote from sgtscott658 >>

If you want to save your sanity, I would advise keeping the people you like and booting the others. Let them know why they are being booted, do not be shy. The Backseat DM needs to go, no room for your vision of the game to be interrupted by someone else. Get rid of the MIA player, no need to design encounters and have it be a waste of time when one person misses out, a real pain in the balls to readjust everything due to an MIA player. If a player annoys you get rid of him, there are a crap ton more players to choose from out there.Basically you do not have to be tethered to players you do not like, or drive you nuts.

Shy players need a lot of handholding. If RPGs are new to them, it will take a while for them to blossom. Some folks don't even, but that's ok. If they aren't disruptive or disrespectful, let them stay.

My opinion would be to definitely not cut the shy player if she is having fun (ask her if she is, but not at the table in front of everyone else).  While it appears you and a couple of your PCs are definitely into RP heavy DnD, her lack of RP certainly won't limit you all in your experience of the game.  I have one fellow that I have had in my campaigns for over a dozen years.  He just doesn't RP, generally is a straight-forward Path of the Totem Barb (half-orc, bugbear, goliath, etc...), but has a blast gaming with the rest of us (even though we are more RP focused).  In the last year he has massively (and tastefully I might add) up'ed his RP skills, and is still having a blast.

The "pseudo-Rules Lawyer" Barbarian is more complicated.  He might have been under the impression this was going to be a campaign that would play "by the book" running published adventures and valuing cohesive and consistent rulings, and now, as you indicated above, it has definitely wandered into Homebrew territory.  He thought he was going to play in one game, but now it is, perhaps from his prospective, totally different.  Might be time for him to move on, or, better yet, might be time for him to be the DM for a bit.

I will be honest, if the Blood Hunter is in fact your DMPC then that would raise a huge red flag for me.  Matt Coleville has a good video on DMPC's, might want to check that out if I have correctly surmised the Blood Hunter's role.  Just my own opinion here.

Any way, have fun gaming!

Hey Easpag... assuming this is a relatively new group. I think forming new groups and games can be hard. Especially when it comes to forming games with quality players. My advice is cut the bad. Find the good. 

a lot of new games have this issue. A lot of new games are a revolving door when it comes to players because of this issue. I would say it is very common. 

on top of saying my advice is cut the bad and find good. To be more specific I would do the following. 

1) I would start by reaching out to the quality players. Tell them “hey I’m not enjoying this game. I think I’m actually going to bring it to an end. At least I’m considering it. I’m really enjoying playing with you and if your open to it I would like to invite you to be apart of a new game I’m going from with different players.” (If you’re replacing a large pool of players I recommend a new game so they can feel like the game is as much theirs as those who stay.)

2) once you have the quality guys secured I would recommend informing the entire group “sorry guys but unfortunately I’m bringing this game to an end!” (Maybe offer to run another session for them and do something crazy like throw down the deck of many or a tarasque awakens. It’s an opportunity to do something crazy no one will forget! Go out on a positive note!)

3) find new players. Start new game. 

I think take out the bad. I was in a similar situation but the problem players had different problems. So I started an encounter but the enemies were focusing on their characters. The characters died and the players left. I told them before the session why I was considering taking them out of the campaign and said if this behavior continues this session then you will need to leave. They didn’t stop so at the end, I killed their characters and went to them afterwards and said I told them that it needed to stop and it didn’t so they needed to leave.

I have a couple of aspects I'm trying to understand.

You are the DM for a homebrew world you created.

You have a bunch of players, some of them with flaws.

One plays the barbarian and apparently also knows the rules well so they answer questions. If they are answering rules questions about what people's characters can do (and people asked) then I don't see a problem. If they are answering game questions about what is going on then you need to take them aside and ask them to not answer questions that the DM should be answering.

There is nothing wrong with being able to help the other players understand what their characters can and can't do, as long as the other player asks first. Also, what did they do to "nerf" their barbarian? Honestly, there are no op classes in 5e so if they play a barbarian with 12 strength then they are just making themselves weaker than other characters for role playing reasons.

You should try and encourage the shy person to participate a bit more.

If one person doesn't show up at all then just leave their character out for now.

You have two folks you consider good rp'ers, the barbarian (you don't mention what else they do besides answer questions), a shy player and one who doesn't show up. There just doesn't seem to be enough in what you have described to justify disbanding the party and campaign or getting an entirely new party unless there is some aspect that you really aren't enjoying about the group ... the only thing that seems to brought up in your post is the somewhat know it all barbarian player.

P.S. You mention "my blood hunter" ... I was just wondering if that was one of the other PCs or a DMPC.