I noticed recently that the ranger class forces you to pick spells from the spell list and only allows you to replace them very slowly as you gain levels. Considering that the druid and paladin (The most similar spellcasting classes to the ranger) can prepare spells from the entire list available to their class on a day-to-day basis, and that rangers are supposed to be versatile and adaptive warriors, shouldn't rangers be able to prepare spells from the entire ranger list like a druid or paladin does?

Yeah I think they should.

As much as I would like that mechanically and thematically, my belief and experience is the ranger spell list is powerful, and making them prepared half casters is a potent power bump. 

Quote from FrankReynoldsGaryGygax >>

As much as I would like that mechanically and thematically, my belief and experience is the ranger spell list is powerful, and making them prepared half casters is a potent power bump. 

 Actually, in my experience rangers are one of the weaker classes, and I don't think a little extra power would be that harmful.

Quote from sfPanzer >>

I don't really care whether they can prepare spells or not tbh. In fact, I'd prefer it if they weren't spell casters in the first place. However since they are spell casters I'd really like to see them as ritual casters and perhaps even have all their spells be cast as ritual even if they aren't ritual spells originally.

 Having all the spells be rituals seems a bit OP, but I think you're right that rangers should be ritual casters. It would be more useful for rangers to cast rituals if they got a few more ritual spells.

Quote from sfPanzer >>

The only spells it'd be somewhat OP for are healing spells. Those would have to be excluded. Or restrict casting non-ritual spells as rituals to a number of times per long rest. 

 What I was thinking was that other casters can't cast non-ritual spells as rituals for a reason. I don't think there's a compelling enough reason to allow the ranger to be any different.

I would like to get back on topic now. If you want, you can make a new topic with your idea.

I think prepared vs known is very diffrent depending on campaign.  If you can easily buy spellscrolls, spells prepared are alot less necessary. So many of ranger spells are not every day ones.

On the topic of ritual casting. More than once I have taken ritualcaster druid or wizard on a ranger. Yes it's a tradeoff but I have found it worth it. Especially beast sense on a phb  ranger. I can blindsight and work with other "control" casters and do more defensively and damage wise than other feats.

because rangers are not prepared casters I think they should get alot more flexibility in choosing animals for purchasing mounts or summons or even creative uses for animal friendship. 

Rangers also can vary their equipment alot better than other classes. Switching your main attack option is like pulling teeth for alot of classes. But within seconds they can change from range to meele or reach. Shields can be changed out for each combat. The flexibility of armor and weapons makes up for "prepared" Imo.

No. 

Their spells are awesome and between primal awareness, subclass spells and spells known they have a crapton already .... including enough daily single uses and slots to be near equal to a full caster of the same level.

Since Tasha's the Ranger is not in need of any more buffing, it is one of the most powerful classes in the game and probably the most powerful so-called "martial" class.  Letting them decide day-to-day whether they should pick between Pass Without Trace, Spike Growth or silence to pair with the 2 other spells they get automatically would be over the top.

Quote from Panda_wat >>

 Actually, in my experience rangers are one of the weaker classes, and I don't think a little extra power would be that harmful.

This was true with the original PHB, but it is not true any more.  The current Ranger is probably the most powerful non-full caster in the game.  Since Tasha's, they are a full on Gish second only to probably the bladesinger in that role, with all sorts of magical abilities, a ton of spells and bonus action options.

Consider by level 10:

1. You can cast 12 spells a day (more with some subclasses). A 10th level full caster can cast 15. 

2. You can go invisible as a bonus action 4 times a day and unlike the spell it is not canceled by attacking.

3. You can give yourself temp hps 4 times a day

4. You have a climb and swim speed

That is all from the class and is in addition to having more skills, expertise and other class and subclass abilities.

I don’t even think they are weak just as handbook rangers. They are stronger in combat now, for sure. But they have never been weak. 

Agreed, rangers have never been weak. They aren’t intended as tanks which makes them seem weak to some but can play the role at least for a while and at their best when played as a striker/controller/disrupter. What is needed more than making them prepared casters is giving the early subclasses ( hunter, etc) a set of subclass spells and perhaps giving them a non feat access to ritual spells.

 I also agree .PHB rangers are not weak usually when someone says rangers are weak it actually means "I cant play them the way I want." But usually there is a class that can play that way. Nature cleric or paladin. druid with some melee flavor. Rogue or fighter built for nature.          

understanding your playstyle and how classes operate in that scope is important. PHB Rangers appeal to tactics, resource management, and solving some problems creatively but the mundane way. rangers adjust to the situation not force one solution on a problem.

If you want to be the run up without thinking and hit things that's a barbarian. If you want huge single target melee that's a different class. but each of those classes is missing options and approaches only a ranger (especially a PHB one can give).

So basically a ranger shouldn't need preparation if you are planning a build around skill/feature/spell overlap. Prepared is nice but usually prepared only makes a difference a couple of times a campaign. {try scrolls or working with the party instead}

The ranger would prepare their spells both in 3.5 and in the D&D Next playtest packets. And I do think a big part of their schtick should be preparing for each day, so being able to swap out spells after a long rest makes thematic sense. By the same token, the rules seem to be leaning in the direction of treating a lot of these spells more like magical knacks.

I think the ranger should prepare its spells. I also think the paladin should just know its spells. It strikes me as weird that they're the only Wisdom and Charisma-based spellcasters who don't prepare and just know their spells, respectively.

No.

Druids and paladins get their spells from a divine source. The spells are given to them by something divine when they prepare spells. To me a ranger is someone who learns skills to survive and fight. He studies and trains to improve his chances to win a fight or survive the wild. He doesn’t serve a divine being to ask for spells each day. To me a ranger can’t wake up, dump the knowledge in his mind, and have new knowledge just appear in his mind.

Divine and Arcane are just old terminology to roughly describe how something worked. Arcane was for unnatural magic, or magic that broke the natural laws. Divine magic worked within the natural law. But that's mostly a relic of a bygone era of the game. Fourth Edition was the only time I can think of them dividing power sources into more distinct categories; adding Primal for barbarians, druids, rangers, and so more. The term Divine no longer holds mechanical weight; other than which spellcasting focus your character can use─if at all.

And in your specific example, neither druids nor paladins need to serve a divine being. Some choose to, but it's just flavor text. You actually undercut your own argument by invoking them.