I don't think gyms would work very well. For one, they reward activity moreso than skill. Furthermore, it's in a gym leader's best interest to avoid matches (except against gym leaders they have not yet defeated) if they're trying to win the event. Lastly, gyms require a ton of matches and people would lose interest over time.
What we need is a tournament. We can still keep the concept of restricting players to gym-style teams, of course.
thisssss
about the AI: pokemon isn't a game that can be played by AI lol, pokemon has too many combinations, gamefreak never spent (and will never spend) much time programming the AI, since it should be really similar to a chess simulator than a game for kids.
the AI of 3ds/any console works like this:
gen1,2,3: pick a move that is neutral/supereffective
gen 4,5,6: like 1.2,3 and SOMETIMES the AI can switch if he can't hit your pokemon with any move
on showdown there are a lot of bots with some comands, but the ai is really similar to the 3ds
about the tournament: i played many tournaments in my "carrier", a format that can fit for the forum is called "smogon premier league" or "elements premier league"
is really inspired to the soccer season (football for someone): X players fights against each other every week, with a calendar: who gets more points at the end of the weeks, wins.
with this format even if u are bad at pokemon u can have fun playing all the tournament, instead of doing only one match.
if u decide to keep the gym system: i wanna be a bw gym/ water or ground gym.