I would say that even renaming the files can wait until we actually have a conflict.  Note that reimplementing enum.py in C will not cause a conflict because that code will likely go to Modules/enum.c or Modules/_enum.c and not in Objects/enumobject.c.  If any renaming in Objects/ directory is in order, I would start with longobject.c and unicodeobject.c rather than enumobject.c.  It is fairly obvious to look for enumerate code next to range code and tab-completion gets me to the right file fairly quickly.  On the other hand, I've been trying to find intobject.c in 3.x code on more than one occasion.