Overall you look fine.
Don't worry about Exp. I actually don't advocate stacking Exp at all in that its a fairly poor stat for both damage reduction and damage smoothing. Since you're hit capped, Mastery is better in both regards, and in fact Haste is arguably superior to Exp. Being at 15% Exp vs 0% Exp is basically 2 missed CS's per minute. Better to put those points into Mastery, an if that's not an option, either Haste or STR.
This. I don't get parried THAT often, even with only 8ish %.
Once you have 7.5% hit and some reasonable amount of exp (probably around 7-8%, there's no soft cutoff anymore), then Mastery gives you better returns. I've wanted to experiment with haste, but since ret is my off-off-spec, I don't have enough haste gear to try it out.