Ok so 3 of the 4 then I'm pretty happy with based on what you're describing:
The Face - Warlock 6 (Fiend, Pact of Blade), Paladin 6 (Vengeance). Feats: Great Weapon Master, Polearm Master. Race: Githyanki strongly recommended.
You'll max Charisma skills, act as the party face / leader, stand in front in melee with enemies, etc. This is the guy who will get any Str boosts you have and any Con boosts you have, but should have permanent stat increases (if any) put in Cha instead since you have so many replace effects (including certain gloves late in the game). You give your party members a save boost, you get 3 attacks per turn + a bonus action attack, 7 attacks per turn while hasted, and you can absolutely nova enemies down with Smite. The Vengeance Paladin and Githyanki are to improve your mobility, though a high Str score, good use of jumping, and haste will do a ton on that end. You *really* want to be hasted whenever possible both for the damage increase and the mobility increase, get potions / spells / whatever will let you do so, and you'll absolutely wreck enemies. Githyanki will also let you serve as a pseudo-secondary on your party's relatively weak Int or Wis skills, which is especially relevant since you're going to face plenty of checks on those during dialogue.
Respec / Levelling notes: I'd go Warlock 6, then Paladin until 10, then at 10 Respec to Warlock 5 / Paladin 5 for earlier 3 attacks per round. Then Paladin for the save boost and finish with Warlock 6.
The Scout - Thief Rogue 4 / Gloomstalker Ranger 5 / Champion Fighter 3. Feats: Sharpshooter, ASI (Dex); Expertise: Stealth, Sleight of Hand
They'll handle Dex skills, act as the party scout, and will absolutely assassinate foes. 4 attacks per round normally, 6 while hasted, +1 in the first round of combat, +2 while action surging. At will invisibility while obscured, which isn't the best that can be done, and no reliable expertise so you're not as good of a sneak thief as say pure rogue or Rogue / Monk would be, but you absolutely annihilate foes in combat. You also benefit from being hasted, not quite as much but still quite a bit, and thanks to frequently attacking with advantage (whether due to being invisible, having high ground, or whatever other conditions you can muster) you should get many crits, which will do at least a bit more than normal damage.
Respec / Levelling notes: I'd go Thief Rogue 4 / Gloomstalker Ranger till 8, then Respec to Thief Rogue 3 / Gloomstalker Ranger 5 for faster access to the extra attack. Add in the Fighter levels for Action Surge and better crits, then finish with the Thief Rogue for the ASI boost.
The Caster Cleric - Tempest Cleric 6 / Storm Sorcerer 4 / Evocation Wizard 2. Feats: Elemental Adept (Lightning), ASI (Int)
This is a direct lift from another thread but honestly I think it's really powerful and would be a ton of fun to play. With the Storm Sorc levels you can twin haste on your primary damage dealers (likely the 2 above but can vary depending on the combat), then while maintaining concentration on that get to blasting, with a quicken create water and a ton of lightning spells at your disposal. It may seem crazy MAD (Multi Attribute Dependent), but you have heavy armor so you don't need Dex, you don't need Str, and while Con, Int, Wis, and Cha are all useful, you're not really using your Sorc levels for anything with a save and the Cleric levels will typically be support spells, so your stat priority is really just Int>Con>Cha and Wis, and those last two can be pretty mediocre and it's just fine. Wizard is where your 6th level chain lightning etc will come from. You get to knock back enemies when dealing *any* lightning damage (even just a lightning arrow dealing 1 point) and can easily blast folks off cliffs and stuff, with good mobility yourself and tons of versatility. Could be Shadowheart or whomever else. This character is the one primarily responsible for Int based skills, though they won't be able to cover all of them typically.
Respec / Levelling notes: Storm Sorc 1 / Wizard 1 / Tempest Cleric 6 / Evo Wizard 1 / Storm Sorc 2 would probably be my pick, but I'm not at all certain about this levelling path yet. You want to start with Sorc for the con save, and you want a level of Wizard early since then you can learn your spells and it scales really well, just a matter of how soon you want your Tempest abilities vs your Quicken from Sorc really. Might want to play around in the mid levels and see what feels good there.
The Last One - Circle of Land Druid 11 / Draconic Sorcerer 1 Feats: Tavern Brawler, Mobile
This is the one I'm by far the most uncertain of. But you want a 2nd caster, you want to utilize how broken Tavern Brawler is, and you don't want to rely on Str and Con boosts already going to the party face, so I think this is the best fit. You get good Wis skills covered, you get to talk to animals (always fun), and most importantly you get 3 attacks per round base with Tavern Brawler applied while maintaining your value as a full caster. Typically you'll want to pop down something like a Spike Growth the enemies will run through (and kill themselves on), only for the Caster Cleric to blast them back with lightning damage (damaging them again) and them to impale themselves again as they walk forward. That is of course anyone who isn't already dead from 1 round of damage from the Face and the Scout. You have +3 AC from the level of Draconic Sorcerer always on, even while Wildshaped, and once you are concentrating on your spell just pop on your strongest (literally and figuratively) wildshape and go to town in melee if needed. You also can dish out some party healing as needed, alleviating the spell slots of the Face and Caster Cleric which are better spent on raw power.
Respec / Levelling notes: You may also want to start with the level of Sorc to get proficiency on your Con saves; you *definitely* want to pick up Haste with your level 5 Circle of the Land spells, that's the whole reason you're Circle of the Land, that and Circle of the Moon forms are not on average higher strength than your base options. Just because the option to have yet another Haste around is always going to be crazy powerful.
There are many other directions you could go with the last slot, but I believe the party above could handle pretty much any situation the game throws at them quite easily and can dish out absolutely ridiculous amounts of damage, very quickly, when called upon to do so. Just my opinions and I've not tested this party composition at all, it's just theorycrafting at this point, so if you do try any / all of these kits please let me know what your experience is like. Thanks!
