Yeah, get yourself a 5D II while you can, they're goin cheap and it's a great back up camera to your mk III. Sell all the ef-s lenses, non IS 70-200 and t4i that should help fund your dream setup!
Setup - 24-70 ii on the mkiii and either a the 85 on the other body or a the 70-200ii. keep the 600rt's handy. Like someone keep the kit light.
For alt flash trigger check out photix oden, or pixel kings as a cheaper alternative to Canon.