Renouncing your Cdn citizenship and just being a US citizen:
the pros:
you can vote for the lesser of the two evil

political parties (wish there were more political parties here; independents have very little power).
the cons:
cannot vote in Canada.
you can't go to some countries (Cuba).
if captured in a hostile country like Iran, Cdns will be let go while US citizens will be held or even slaughtered.