Balance issue: Concentration spells are ALL nerfed to oblivion because of the abundance of surfaces. I'm not going to use Bless or Blur when a Fire surface arrow or bomb from a random goblin will make me roll for concentration three times. The only good option is to have less surfaces. Making concentration checks easier would overpower the same spells in other situations.
Or just reduce the difficulty of concentration checks caused by surfaces, specifically.
Or even make that surfaces don't break concentration since most of the surfaces are Homebrewed in?
