I don't like Governor or Minion as their different options self-synergise into a single card strategy.
If you play minions as a single card strategy, you're doing something pretty wrong.
I was about to say the same thing about Governor. Governor is a very powerful card and lends itself to a decent single-card strategy, but on pretty much every board there are other cards that complement a Governor deck. Even if you do only buy Governors, that's still not a trivial deck to play given the number of decisions. I personally think Governor is one of the hardest cards to play optimally, and it's a top contender for my favorite card in the game for that reason.
Anyway, I really hate Rebuild and Tournament. Rebuild for the reasons everyone's been saying. As for Tournament, I hate the first-come-first-serve mechanism, I hate that someone can get a lucky $8 hand and suddenly snowball into an insurmountable lead, I hate that one player getting a Province or two not only means they can get Prizes but also means they can turn their opponent's Tournaments into Ruined Villages. It's not as bad as Rebuild, but I still audibly groan whenever I see it in a kingdom.
How about a favorite cards thread? I'd rather talk about that.