Just a quick note on that dragonite. Extremespeed is illegal with multiscale so you can essentially scratch that for a bulky dragon dance set. Also no attack investment will be okay as with the bulk you have at least one dragon dance will be accomplished.
Look, choice scarf makes yanmega difficult to revenge kill and makes him a decent revenge killer. As long as you have tinted lenses, all you have to do is click on bugbuzz and airslash.
However if you don't like the power of scarf, then there are 2 more sets, one is a set of substitiute with sub + 3 coverage moves along with life orb and the other is the dreaded specs-mega holding choice specs + 3 attacks + u-turn. specsmega has a lot of power. infact it can 2hko quite a lot of stuff. if you really want power at some risk go for specs-mega.
uh, this is not a bulky set..