What happens if AD and AP end up having the same amount of numbers

Now lets give an exemple: What if a final build for an AP champion with ap items becomes 300AP Max and an AD champions 300 AD Max. What would be the biggest difference? AD can crit and AP cannot Crit, Riot if you are going to keep toning AP on AP items, I hope you remove Crit from the game and tone down lifesteal, Ziggs for exemple is a good champion but poor scaling he comes from a meta where AP items used to give him about 1k AP per matchs, Now he does barely any damage and is very very poor in term of how useful he is to a Team,

Now for my 2nd suggestion give Mages 50% auto attack scaling with AP. Just to make Csing easier and more fair, because I'm sick of looking at a yasuo miss 0 cs.