You could also trade off things that were more important in the ancestral environment than they are now. For example, social status (to which the neurotypical brain devotes much of its resources) is no longer the evolutionary advantage that it used to be.
You two realize you are just reinventing Bostrom's EOCs, right?
People, I wrote a thorough essay all about this! If I left something out, just tell me - you don't need to reinvent the wheel!
(This goes for half the comments on this page.)
Just thought you guys should know about this. Some work that argues that humans should not enhance their intelligence with technology, and that super intelligence probably never evolves.