by StagCutlery
1). If you have 3 cards in your hand, then I don't think you can use Stolen Wisdom because of the same reasons explained above me. If you have 2 cards in your hand (or less), then you can use Stolen Wisdom, and this will leave you with 4 cards in your hand if you started with 2.3). They gain an Ally, you gain Power (as if they 'hired' the ally from you and "paid" for it).
4). I'd like to see a ruling on Weapons Cache because I don't remember a use limit on anything except Specialties/Infinity Stones.