That's a nice team you have there IndianaJones. To be honest, when a team that relies on weather loses the weather war, they more often than not will lose? With that said there isn't much you can do about venusaur? I would suggest running a spinner on your team since you have two guys weak to rock and four hit by spikes which is very problematic if you switch around alot. The pokemon I have in mind is tentacruel since he benefits from rain wiith rain dish and also provides a check to volcarona and tornadus and toxicroak (though he wont be doing anything to the latter w/o a super effective move). Imo it should go over rotom.
Staraptor is also a rare sight in OU, but regardless you do have adequate ways to deal with it. I'm also curious about the evs you placed on scizor. Most people max out its bulk by investing in hp and stuffing the rest into defense which would give you the staraptor check you're looking for. Good luck with your team!