I can't help but wonder if George W might have handled some of the issues Cheney bungled a bit better - the Iraqi insurgency and counter surge, the housing market crash, Katrina, all those Congressional Scandals, etc etc. At the very least, I doubt Bush would have has a fatal heart attack after the 2007 Market Crash like Cheney did...
On the other hand, Vice-President Powell did marvelously for his brief time as President... wish he'd have run in 08, it would have spared us President Edwards...
What about pop culture - we all know a bunch of celebrities basically got black listed following their 'celebrations' following the assassination. Green Day, Seth MacFarlene, Jamie Foxx, among others - how might not making jokes about a recently murdered President had bettered their careers?