Note that the entirety of xorg-based dependencies for tk number at 17, but half are proto ports (just install headers). If it's disk space you're worried about, all of those take about 12M of space (most being xorg-libX11), which is about 1/5 that of just python26. For build times, those proto ones are extremely quick and the rest are quite fast as well (again, especially when compared with python26).
Aside from those bits, what other issues do you have with tk bringing in these dependencies? I ask because I've heard once or twice that tk+quartz may have problems with python's tkinter.
