The only thing I miss from the 7D is the 'spot focus' option which does help in certain circumstances. However, I was also shooting for a time with a 1D3 and that had full point focus so has helped me get used to it again. The 70D AF system has more basic options but you can still pick single, multi or all focus points, although I mainly stick to single point I use multi point for BIF as it's good for tracking. I can get very clean photos at ISO1600 and very useable photos at 3200, it only starts getting bad after that, but you can still see lots of subject detail at 6400 although the background is noisy but a lot of that could be removed in post.
I got mine from L.C.E. for my 7d and another 1D that I'd just been given but wasn't using so I jumped for it. I'm using the 70D in far more situations than I ever did with the 7D. Most of my macro shots are now with the 70D rather than my 5D3 and I'm about equal in bird shots between the two.