The novelty of Shane was that he was surprisingly athletic and a leaper, and that he was surprisingly good for a non-wrestler. But most of his offense is built around adding jumping to moves that looks like he jumped just to show that he can jump. I remember a weak chair shot where he showed he could jump, just to make contact to the person’s head with the chair. That doesn’t make him a good wrestler; that just makes his offense look stupid and drags down his opponent.
He looked great in the match with Angle and he has had some truly exciting matches over the years. But a good wrestler he is not. Overexposing him by making an active wrestler would have just been horrible for everyone, and even more so because you know he would have racked up a lot of wins and titles over better talents.