Given that there is some speculation that the Minish Cap occurred before OOT, this could be one of his later exploits, after he became a sorcerer.
After he bacame a sorcerer, he morphed into a big shodow-blob-monster and got locked inside a sword.
The Four Swords series covers essentially Vaati's entire lifetime, and there's really no room for any other ventures.
also, SPADE GIRL. *waits for someone to inevitably design more card-based characters*