@Horwath
Current thoughts on attack differentiation:
Fighters just straight up get 4 attacks on any targets with no limitations.
Marshal gets 3 attacks, but the ability to give other players some of their attacks, increasing tactical utility.
Rangers get 3-4, and are incentivized to burn more action-economy on a single target, rather than striking multiple targets.
Paladins and Rogues get 2, and are incentivized to land their hits by adding in big damage drops (Paladins half as much on each attack as the Rogue on one)
Barbarians get 2 and are incentivized to swing a big heavy weapon to maximize their damage, with additional secondary-target hits for AoE.
Monks get 6 unarmed strikes, each for low damage, but add their modifier to every damage roll bringing up the damage dealt through guaranteed rather than random values.
Artificers, Bards, Bards, Druids, and Warlocks I'm not exactly sure how I want to handle. But I'm pretty sure they're all going to get two attacks in theory...
And then Sorcerers and Wizards will get 1 attack each.
Yeah, 3e's structure was preferred to 4e's structure for martial characters. And I'm fully aware of Rogues with Sneak Attacks and Paladins with Smites. But it would also create -less- diversity in class function rather than encouraging more diversity in function, which is my primary goal, here. Making the classes feel different in how they play against each other while retaining a semblance of similar DPR.
As far as the elegance of accounting for Str or Dex or Int or Cha or whatever mod being applied multiple times in a turn, that's just something you have to take into account when designing the classes. 5e didn't do a great job of that. Vis a Vis the monk getting scaling damage on unarmed strikes to 1d10 with Str/Dex on every strike.
Which is a big part of the late game HP explosion that happened. With the sheer amount of damage flying around in every direction you need massive sacks of HP to last a few rounds against it all.
A5e introduced the concept through Shields, making them much more important for "Tanky" characters. I think it's a good idea that mirrors Thorin Oakenshield's whole schtick, but feel like there's more to be done with it.
I actually put a whole Social Combat system into Martial Artistry if you wanna go grab a copy and take a look. It's on DTRPG.Com.
That said, I wish I'd taken more time to iterate on it 'cause I have a better handle on how I'd do it, now.
Yes and no.
There's sacred cows like 9th level spellcasting. The intent is to keep those sacred cows while reducing their mechanical power. A 9th level spell in this system concept is not as strong as a 5e 9th level spell, even if the name is the same and the broad general function is the same. Meteor Swarm, for example, would still call down a bunch of meteors each doing an AoE, but the damage of each would be scaled down to a game where 10HD Player Characters is the high end.
Proficiency Bonuses keep increasing to +6, though, for players and NPCs as well. To keep some level of there being strength of level over lower level creatures. After all when you have 10 d8 hit dice, a bunch of Goblins is a lot scarier than they are when you've got 20. But the party Bard's Enthrall save DC is gonna be high enough to shut most of them down.