Not quite sure if this belongs in general, variants, or puzzles, but whatever.
A long time ago, back when only the base set existed, I played a game where we put out all 25 Kingdom Cards (we were also playing with 6 people). It wasn't a whole lot of fun, but anyway...
If you were playing Dominion where you laid out every single Kingdom card in existence, instead of just 10, what would the dominant strategy be? My guess is that you'd want to open Chapel/Quarry, then pick up as many Goons, Watchtower, and Fishing Village as you can. Likely, whoever gets the most Goons would win. What else would you try? Would cursing attacks be worth it, if Curses could be so easily drawn and trashed?
Black Market would certainly lose a lot of its value, though you could still pull off double-Tactician tricks with it.