We play by the book but there are some things I find lacking/annoying.
Concentration checks are too easy. Using DC 10 or half damage, whichever is higher, is too low. Once you get past lower levels, especially.
Adding in War Caster, as others have said, makes it even worse.
I would estimate, maybe 1 in 4 or 5 spells are ended because of failed Concentration checks. At higher levels, once Resilient (if needed) and War Caster are taken, it is closer to 1 in 20 or so.
I have thought about some changes:
- The check to DC 10 or full damage, whichever is higher.
- The check uses your spellcasting modifier (instead of a save), so you are automatically proficient.
- You can concentrate on a number of spells equal to your spellcasting ability score modifier.
- If you fail a concentrate check, you lose all concentration spells you have active.
But, I am still thinking about it.