In a Peter David novel he was.
Kirk managed to render him powerless by destroying his amplifier machine, so his abilities were technology based.
Trelane's parents seemed less bound by technology, but they didn't bother showing off either.
I think the strongest contenders might be the Organians.
By everyone else, even the Borg, Q would be pretty untouchable and the best the team can hope for is a stalemate.