Making it a Potion cost card has the curious side-effect of occasionally making the treasure-trash part less powerful (you could have drawn another Copper, but instead you drew a Potion). At the same time, it offers its own way to get Potions out of your deck when you no longer want them. That sort of tension makes it an interesting Potion card, if nothing else. I'm not sure this balances out all that well using the Tribute setup. I imagine trashing Actions won't happen all that often, and next to never in quantities great than 1 (save in Ruins games) and even when you do manage to trash multiple actions, getting all of those +Actions is hard to use since, you know, you're trashing Action cards. I'd consider taking a Transmute route instead, where you're cycling cards into other benefits. So, like:
Action, + Cards
Treasure, + Actions
Victory, + $
I just feel the options become more interesting like that.
