Okay, thanks for the advice. I'd basically stayed away from Cathedral before, but I seem to lose more often when it's available and I don't buy it, so I decided to try it and it didn't work out. I'll keep trying to figure out how to play with it; it seems pretty good if you can play it right, but it's a little tricky to figure out.
A few more questions, since I couldn't find an article on Cathedral:
1. Should I buy bad cards like Coppers with extra buys to prevent a bad trash, or just not be bothered if it forces me to trash an engine component, and buy a replacement with an extra buy after the fact?
2. Should I wait for second shuffle with a 5/2 opening or pass up the Cathedral for a

-cost, or get it the first chance I can? 3. As kind of an extension to the second question, what about a 4/3 opening? Do I wait for the second turn, and get a

-cost?
4. What if there's no +buy or extra gains on the board (although that doesn't apply to the game I played)?