I'll just add that I've never missed reactions in previous D&D games that use older rulesets. BG1, BG2, NWN... I'm not convinced reactions are needed in the first place. And they seems to be VERY difficult to implement properly in a CRPG, even a turn based one. Something for designers of 5.5 / 6e to think about for sure. I think it's pretty obvious there needs to be less reactions overall if they are to remain. And less spells requiring concentration.