Put higher level caps in Unova, level 56 after beating 8 gyms it's just too low, it's the lowest of all regions; and, considering that during the battle with N, after you have beaten the Elite Four, you MUST have Zekrom at level 52, so a lower level pokemon (since all other will probably be at 56) this is even a bigger handicap. Or make N's pokemon less powerful, that's another way. Also, if you decide to not change that, at least do not make players battle with Zekrom EVERY SINGLE TIME to capture him, after N beats them. I mean, what's the point of capturing Zektom 4-5 times? It's just a waste of money (to buy pokeballs), time and patience.