Doomy I'd say it's 5-5, 6-4 at worst only because it can be hard to run from him but Savage Blast helps with that. Also, up arrows make Supernova useless. I think GA vs. Doomy is basically the same as it for the rest of the cast. If you can't block earthshaker, you're going to have a hard time.
Supes vs. GA is definitely 5-5. I'd actually put it in Arrow's favor if it weren't for Supe's damage potential. But, I feel Arrow controls the air taking away a lot of Superman's offense. His wake ups are also easily punished.
Only losing MU's I'd give Arrow are Bane, Zod & friend, MMH, & Raven.