I hope to have a team of fully evolved starter Pokemon, one from each generation. The Pokemon I choose depend on personal preference and whether or not Fennekin becomes Fire/Fighting. (Should that happen I'm swearing off Fire types forever.)
Even if older pokémon are available right away this generation, I want to try and avoid using them in favour of the newer ones. I've started avoiding pokémon I've used before in playthroughs lately, unless its one of my favourites.
So... Fennekin Evo New Flyer New New New Cover Legend (if it can be caught before post game)
Although assuming exp is as generous as B2/W2 this team might end up being a bit bigger.