I'm literally gonna do a random number generator to choose mine. It seems more true to how it would go in the games, and it's kinda fun to not have total control ^_^
I did something similar with a Random Pokémon generator since it saved me the effort of assigning each type to a number, though I didn't go completely random. The first Pokémon I got was Chesnaught, and since I already decided not to make hidden power grass type, I went with fighting but realizing how Nathan would feel with another move useless against the red-eyed Pokémon I rolled a second time and got Vaporeon.