Homosexual cyborg.
Either that, or just an old fashioned technical pro. His schtick always seemed to be that he had something to prove; like he constantly had a chip on his shoulder about being smaller than a lot of the guys, or from a different country, or not being as flashy. He started off with a noble underdog kind of gimmick and ended up being with a bitter, jaded, ego-maniacal crybaby gimmick.
His family heritage played a large part of his gimmick. Being Stu Hart's son, they made a big deal about his role in the Hart dynasty. He was supposed to be this special kind of grappler who'd learned his trade in the infamous dungeon and had a counter hold for everything you could do.