Thanks for the feedback guys.
I agree the wording on the bottom is clunky, but I also want to avoid making this a Duration card if at all possible. It feels pretty wrong that the Duration part of this card would be purely downside, and Durations also tend to miss reshuffles which I don't really like. I worded the second downside as a "discard down to 3" so the card can self-synergize a bit (playing additional copies won't hurt you more) and also to make this card kind of a delicious combo with Outpost rather than just sucking with Outpost.
Regarding gaining a copper - here are the reasons why I chose Estate:
1 - Estates will empty sometime, likely after the Curses do. This card is very sad when Curses are gone and at least it's just an expensive Smithy once Estates are out too.
2 - Estates cost $2, curses cost $0. There might be some interesting strategies where both decks are being junked up but trash-for-benefit cards generally work better on Estates than Curses.
Gaining coppers has merits too, though, I will have to think about this one.
An alternate downside I was considering was "... or draw only 4 cards (instead of 5) during this turn's cleanup phase". It's probably too brutal though.