I don't think casters need buffs either. They don't need 2x concentration. I think casters need:
1. To have their obvious bugs fixed so things are actually working as intended within Larian's homebrew (which already includes some nerfs to CC)
2. I would actually say that after that, casters need some NERFS. Enforcing the one-leveled-spell per turn rule. Haste might impact martials more, but it is in fact a buff to a spell. That needs to be nerfed. Wizard subclasses need to be reworked because some of them are really good while some are terrible. I *play* as a diviner wizard in BG3 and I think it needs to be nerfed. 9 portent dice a day is absolutely busted.
That's the thing, I don't think anyone needs buffs. I think there needs to be some across-the-board nerfs. Tone down some of the absurd martial gear that allows you to stack tons of additional die and damage types on top of your melee hits. Nerf the consumables. Nerf the stupid gear you get that turns magic missile into the best spell you could cast 90 percent of the time. When I play a caster, I want to feel like I'm choosing the right spell for the situation. I don't want to feel like the game is telling me "You're an idiot if you don't spam MM because of the absurd gear we gave you."
Because the thing is, even with the bugs that make spells not work properly, right now this game is *absurdly* easy. And I don't want people who are currently playing on tactician or balanced or whatever to feel like I'm insulting them, so let me clarify I'm a person that has a lot of experience with these types of games. If you think tactician or balanced is good fun, that's great. But I think that as you play the game, and you become more familiar with its systems, you will reach the same conclusion I do: This is a *very* easy game. In fact I will go a step further: I don't think I've ever played a game of this type where the maximum available difficulty felt as easy as this.
And the problem is, because of a combination of Larian's homebrew and the absurd items they give you, it's actually going to be *hard* to come up with higher difficulty in the future - hard, that is, without taking the laziest route you could of simply absurdly inflating monster's statistics. But it's a sticky situation because you can't do across the board item nerfs - which is what I REALLY think is needed, more than anything - without impacting the people wo are currently enjoying lower difficuties.
Maybe a solution is that they could actually have versions of items specific to each difficulty level. Like, an item that adds 1-4 fire damage to melee strikes on story difficulty, would add 1-2 on balanced, and only 1 on tactician, something like that.
But yes overall I think that trying to put casters more on par with martials by buffing them is currently a very, very bad idea. Fix the obvious bugs, figure out some way to nerf the martial-centric items.
And I said this before....but uh, if you have Karmic dice on....isn't the way they work an inherent buff to martials and an inherent nerf to casters? The way I understand karmic dice is that if you get a low roll, you will eventually get a high roll. Or in other words, it skews the distribution of rolls so that while you can still roll anything, you are a little weighted towards higher numbers. But it applies to both your characters *and the enemies.*
Am I wrong, or is that inherently something that favors martials? Because martials will often be rolling against an AC to hit, and be more likely to succeed. However, for spells, most of the time it's enemies rolling against the spellcasting DC to save - and they are more likely to succeed.