I suppose a possible guide to what a Perot presidency would have been like would be Jesse Ventura's governorship in Minnesota.
Perot probably wouldn't have been an awful president, but I doubt he would have got much done, and would probably not have run for a second term. Whoever picked up the third-party torch in 96 would probably have got a decent vote by third-party standards, but not have come anywhere near to victory.
Nah, he'd probably do a bit better than Ventura... he had decent relations with the press, right? And could he compromise once in a while?