IMO, probably strong, but strong trashing with ANY village is probably better than just Plaza's discarding for getting the full benefit out of PH. But Plaza is probably among the better villages when strong trashing isn't available. For example, hand is Plaza PHx2 Copperx2. Play Plaza, draw a non-Treasure, discard a Copper. Play the two PHs for $3 each, play Copper, use your new coin token and get a Province. Plaza removes treasure from hand and also grants coin tokens to give you a bit of extra left to hit $8 when you can't quite get rid of all Treasure. Of course, Hamlet can also discard treasures from hand, with a bonus of providing +Buy as well, which can be nice if you are playing tons of $4 PHs.
