From what I noticed that in PRO grinding is bit easier then in original games of Kanto - Sinnoh, because it feels I get more experience then in original games, more wild Pokémon appears including evolved ones and there is even Halloween 5% experience boost atm. So it not so hard to grind in PRO, I think. The hardest part for me in PRO it's that it's online games, so if you caught bad IVs/Nature Pokémon you can't reload save.
Yeah I understand that bud but not everyone has got that far to bear the e4 why can't they get involved in the ghoul swamp event? Bit unfair in my opinion that ur required to beat e4 just to do an event which shud be open to everyone