He'd be great in a Pirate deck that wants to steal everything, but he should be given his own deck that supports a theft strategy
Brawl Legal Vintage Legal Timeless Legal Commander Legal Pauper Not Legal Oathbreaker Legal Penny Not Legal Toolbox Buy This Card Notes and Rules Information for Snapcaster Mage: "Flashback [cost]" means "You may cast this card from your graveyard by paying [cost] rather than paying its mana cost" and "If the flashback cost was paid, exile this card instead of putting it anywhere else any time it would leave the stack." (2021-03-19) You must still follow any timing restrictions and permissions, including those based on the card's type
Deathtouch is a strong choice for the ability because that means that as an undersized creature it can still trade when it has to and is unlikely to go dead, and if youre using Auras, you can combine this with either trample or first strike to good effect
-2: Tap up to two target nonland permanents
My only knock against it is that you cant play it in a Hakbal of the Surging Soul deck
Also, your curve is a little heavy on four- and five- mana cards