I think what would help allot, is if there is a symbol or something, floating over the character to show that the character is concentrating on a spell. This would be nice on enemies as well. It is rather stupid that I have to click and examine a character to find that info.
The same it is if you try to figure out how high the "Spell Save DC" on a character is, there is no spot in the whole sheet. You have to dig around to find it.
