I had never really appreciated the concept of Counterspell until now. Characters that are able to see the actual spellcasting get to roll an arcana check to identify the spell, and then if any one of those characters have Counterspell, they get the option to counter it. If you fail the arcana check but are still in range to interrupt, you can still counter it, but you won't know what spell you're trying to halt.
There's a lot of strategic layers to unpack here, and that's just weighing the risk of stopping a spell or letting it continue - if you even have a reaction available to counter to begin with, and the enemy didn't bait it with something like you using Shield or an opportunity attack beforehand.
Also, I had been previously concerned that Solasta was actually pretty easy before. This patch made some fights brutally hard, but still feeling very fair within DnD rules (it's almost like you are encouraged to use everything you can when you don't have a blatantly easy answer like shoving an enemy down a cliff isn't thrown in your face in nearly every fight). Almost feels like I'm playing a X-COM game at times, really - and those games are considered the pinnacle of tactical turn-based combat for a reason. The below is a level 4 boss fight, and I came dangerously close to a party wipe - but managed to turn it around with some quick thinking. Granted, I did not come into the fight with stealth because I had grossly underestimated its difficulty (and I really should have been blasting them all with Scorching Ray).
That said, one could argue that BG3 combat is lacking partly due to the fact that we're capped at level 4 there, and will probably stay like so for at least another year. Solasta's full release is estimated to be within the May-July period, so Larian will have plenty of time to take some notes before finishing development on BG3. (I say another year for BG3, because no one sane should really want BG3 to be finished this year. Unless WotC is spiteful enough to force Larian to rush it out the window to directly compete with Pathfinder WotR, which will most likely release in the July-September period - and it would be a fight that BG3 in its current state would most certainly lose.)