[Brilliant Diamond & Shining Pearl] Need help getting to 100

[Pokestar1033]

So I was wondering if anyone knew a better way to get your team to level 100? I battled the gym leaders twice and maybe it resets after day but it won't let me battle them a third time and I have been grinding the pokemon league and have my team close to 85 but it is very slow going even with the lucky egg and since they patched the glitches I am unable to do the rare candies.
Does anyone have any tips?

 

[Sheep]

There's an Ace Trainer on Route 228 who has a Lv. 54 or 55 Chansey on her team, if you use the VS Seeker + Lucky Egg you should be getting some pretty good exp with each battle! Here's the original source for this info.