I mainly do composition and the like. I can rotoscope, and I can also make mattes (but not nearly as well as Angel can).
Most of my work is in moving video - motion tracking, rotoscoping, etc.
As far as CGI goes, most of my work is just in the composition, as I mainly used 3D models from Sci-Fi 3D. But I could definitely render them more realistically and such.
Basically, I can do a little bit of everything, and I'm pretty confident I can at least partially do many of the visual changes you would like to do. I can't know for sure until I know what will be done shot-by-shot.