I think it's fair to say that Legal Practice is very arguably the worst Hero card in the game. Giving a Hero the ability to remove threat on Alter-Ego is certainly powerful in concept and it follows that the payout should possibly be lower or the risk higher, but in practice (heh) Legal Practice is far too costly, especially in a Hero who is already gimped by a small hand size. The best case use for this card is as an Emergency to prevent a main scheme flip, and it feels bad that a Hero card is barely situationally better than one of the worst neutral cards in the game.
Sadly, this card almost single handedly does more to hurt She-Hulk than even her Hero hand size. It's a dead card often, mostly used as a blank resource.
I would love to see this card errata'd to read "remove 1 threat from each scheme for each card discarded this way."
What this does is it leaves Legal Practice as a bad card to use simply on the main scheme, but it offers some massive scaling depending on how bad your situation is. With a single side scheme out, it's on par with Crisis Interdiction. With 2 or more side schemes out, you could even sacrifice your whole turn to significantly wipe threat from the board, which seems like a rightly strong thing for a Hero card to be doing, giving it the Jessica Jones effect of being more powerful the more schemes are in play.