We do get some psionic tadpole abilities that can make having a weak concentration spell active give more of a payoff, but it's a bit one dimensional, like just for a damage punch to wrap things up. The concentrated blast one I mean. Every now and again someone still has guidance up and it's like 'oh wow, bam!'
Interestingly, that can actually be more useful for a PC. Since if you take the place of Lae'zel in the Zaith'isk and succeed in the skill checks, all tadpole powers become bonus actions. Allowing Concentrated Blast to be effectively a guaranteed hit Cantrip when combined with using a Standard action on something like Guidance or True Strike and then using your bonus action on Concentrated Blast.
It's still a bit niche given things like Eldritch Blast... But it can be useful for Clerics and Druids whom don't get good offensive Cantrips (Spore Druid gets Bone Chill at least), saves you having to pick up Spell Sniper (And dealing with the annoyance that is the inability to put spells obtained by feats onto the Custom action bar to be able to use keybinds to select them...)
It's tough cause I'm sure any change to core stuff as written here would raise eyebrows, but the concentration dynamic is just one of those things that doesn't really grab me, least in the BG context. Takes a lot of getting used to.
Aye. BG3 is bound by DnD rulesets. Which while somewhat lenient (Larian has done a lot of homebrewing) still has some basis from which to design from. Which leads to various oddities (Amplified by Larian trying to do their own thing as much as they can which can create even more strange interactions)
ps. another issue that I always have, which probably plays into my impression here, is that whenever I'm the full caster I don't usually want someone else cramping my style or stepping on my toes. Like probably I should have had Gale as some sort of vile S'wizard to twin cast the Haste so I wouldn't be tempted to do it myself.
Personally I've never had such problems. I have no issues with having 2 similar characters in a party (My only concern is ensuring that characters don't compete for items, but there's plenty of caster items to have even a full party of casters without issue)
Nor have I EVER been tempted to use Haste. Like, I can make 1 character attack a couple more times? Great... OR I can lay down a Wall of Fire and burn EVERYONE to a crisp?
Twin Haste can be more competitive, as you can make 2 characters attack more... But at that point why don't I just go all in on the best Haste provider in the game, Spore Druid? Where you can get the robes in Act 3 that let you use Haste Spores to give your enitre party Haste without concentration...
if there was a 5th character hehe.
If you're on PC, you can mod that. You can have even more than 5 people in your party if you wish.