My qh looks pissy too at times. Especially when she's in heat.
I tried lots of different stuff with my qh ((competitive) trail, western, working on cows, jumping (tiny), dressage currently). I could tell dressage went the best: she seems to enjoy "showing off" in ring. While she obviously hated cows and going out on trails.
My other horse likes pretty much anything because she's easily excited and just enjoys new stuff: she loves trails (even though she's rather spooky), she's all excited about jumping, and she's OK with flat work (not something she loves though as it may be somewhat boring for her).