I should write something on Stella.
Most of the reviews are off the mark, as judgment and even as description. Roberta Smith's review is the best, and the only one that doesn't smack of moralism.
Stella is the most important American "fine" artist alive. That's my bet, though I'm going to be around long enough to find out if I win. But he's made a lot of work and he's made a lot of crap, and critics and other members of the self-described sophisticated audience for art (as opposed to film etc.) still follow preferences based on their ideological positions. Smith's tastes, within her preference for abstraction, are more catholic than most.