RAW stills from a 5D II are 25-30MB. Where did you get 48?Whoa there, cowboy.
Don't care about Filesize? Imagine an uncompressed frame is 48mb... that's PER frame. RED's more compressed than that, so yeah, file size is important. Conversion process takes time, time equals money.
And, "bad" depth isn't fact, it's preference. Most of Slumdog was helmed on a 2/3" format. There's nothing wrong with it. If you don't have anything to shoot that's good, wont' really matter.
Otherwise, I can see where you're coming from. The closest I think we'll get in the next three years, however, is an S35 scarlet, and that sucker'll set you back 15K at the least, I believe.
Wee~