a couple of things spring to mind:
A) python would have to be in base then. the license seems to my amateur eyes as a BSD license with a tamed-down djb clause #3. perhaps the license excludes it from consideration in base.
B) making the ports infrastructure make constructive use of the bittorrent concept might be complicated. some packages are quite small; some packages are quite large. people are going to have to sit around seeding forever for some of them for there to be any difference from just going FTP...
Jeremy