One of my favorite Pokemon to battle with in an RP is Beldum. He's a good sturdy Pokemon that can be used in a creative manner to take down opponents. Turn-based combat would be rather dull, as limiting Pokemon to only their moves is just people not wanting to allow extra creativity in combat. I could never get into a Pokemon RP like that, simply because I'd get bored, and probably lose interest. xDD

I never liked any sort of ability that truly gives me an edge over my opponents, in PvP or PvE. And honestly some of the Mega designs are outright terrible, like Heracross. I can't get over how Mega Heracross looks, it's just... Dumb. xD

By chance are any of the Professors coming to do any research? If Desmond was to meet Professor Rowan, he could learn about Mega Evolution that way. I'm certain that after what happened in Kalos with Pokemon Mega Evolving, he dove into studying it. I always like that Rowan focused on Evolution. Pretty neat, imo, to have so much interest in just one aspect of Pokemon.