I've been playing D&D 3.5 for over a decade, but lately I'm trying to make the leap to 5E. I've made a Ranger and a Cleric so far, but really all I did was take the vanilla character from this website and added a character name to it. Now I'm trying to make my first original character for a PbP campaign.

CharOp is a low priority, because it's for PbP, but I don't want the character to be more dysfunctional than it already is, and I'd like the build to complement the fluff.

Here are the Creation Guidelines:

Step 1: Choosing your Class
Any class from an official Wizards of the Coast book is fine. UA by approval.

Step 2: Choosing your Race
Any race from an official Wizards of the Coast book is fine. UA by approval.

Step 3: Choosing a Background
Any of the backgrounds in the players are fine to use, if you have found another somewhere else, I will need to read through it to see if it fits the setting.

Step 4: Assigning your Ability Scores
This is standard 27 point buy and standard arrays.

Step 5: Choosing Skills
Gain an extra skill from your class skill list.

Step 6: Choosing Feats or taking Ability Points
This campaign will be starting at level 3. Also, take two feats that fit your character thematically.

Step 7: Choosing Equipment
Characters will be starting at level 3 and with 100gp to spend on extra equipment. If there is something you can not get from that but would fit your character to have, let me know and we'll talk about it and see if we can not agree on it.

... and here is what I've created so far.

I'm going for wild eyed mystic, made insane by his profound discovery and no one believes him. He lives in squalor while in the city and tends to make homes in caves or burrows when he lives in the wilds. He eats bugs, roots, and berries and is short and kind of scrawny, but wily and tough, which I reflected in his ability scores. But I'm struggling with gear and feats. I've been given 100 GP to work with apart from my starting gear, and this link for Feats. 

I know weapons are weapons... just pick something good for DPR and run your fluff through RP, but I feel like a weapon is kind of thematic too. I chose Greater Weapon Fighting style, but that means I need to carry things like greatswords or battle axes, instead of Finesse weapons, which makes more sense for the build and the fluff. But I want him to be able to imbue his magic through his weapon, which tends to be a cooler concept in melee. Maybe I should switch to TWF and wield two daggers? I feel like bows, spears, daggers, or things that could double as survival tools might make more sense for a guy who travels light and spends a lot of time outside the city walls, since he is in almost every conceivable way a social pariah. 

And as for feats... I'm 100% at a loss. I just don't know how to build this scrawny, wily, scrappy, wild-haired, wild-eyed, giggling, drooling weirdo. Help?

From that link (incidentally, gah), you might consider Beast Slayer, Blind-Fight (even I come up with better names than that), Catch Off-Guard (I'm not going to repeat myself), Darting Strike, Deft Hands, Dirty Fighter, Dodging Expertise, Eagle-Eyed, Fleet, Fortuitous, Herbal Healer, Improved Initiative, Lightning Reflexes, Lightning Stance, Mobility, Sidestep, or Stealthy. 

Can't see the link...

 I hyperlinked it. Maybe your browser or anti-virus software isn't letting you navigate away from the page through hyperlinks. Sometimes anti-viruses can be finicky that way.

Here is the actual URL: http://www.5esrd.com/feats

Yes, I agree the feat list is kind of... ugh. Especially coming from a 3.5 perspective. But based on how 5E characters are stacked up from level one, I'm not even sure if feats are even necessary anymore. But I digress, and I'll probably know the answer to that line of query when I am more experienced at building 5E characters.

sorry, I meant for your character.  I can't see anything about them.

That's odd... I built it right here on DNDB.

Here is the URL for that, then. https://www.dndbeyond.com/profile/Inexorabletruth/characters/1803635

Characters are currently only viewable by the Player who "owns" the character, the DM if they are in a campaign here on DDB, and moderators.  The rest of us can't see them, even if you provide a link.  That's because currently they don't have a way to allow for "read only" viewing; right now anyone who can see your character can edit it.  You will need to make a screen shot to share if you want us to see it.

The ability for "read only" views of characters has been requested, and I think it's on the list, but I don't know how high a priority it is.

Ok... the DM wants my character ported into another format anyway, so I'll present the link once I'm done with that.