Hello, this idea was really good and totally possible in this game.
This game doesnt follow any other meta game, and with the Mega evos could be a great idea create the council. Also for a future "Tiers".
A council with tops players + staff members to discuss about competitive mons, abilities and moves sounds pretty good.
In addition, with a good council we can create more diversity in the game and much more unique strategies.
[spoiler=Examples]
To add examples (obvious examples) I want mention Greninja, a UBER pokemon in gen 6 metagame (with megas).
In Pro, Greninja is really far to be this Uber poke. Its just a good pokemon, but not broken or unbalanced.
Another example could be Mega Mawile and Mega Metagross.
Mega Mawile was uber in Gen 6, but OU in Gen 7.
Will be banned in PRO? We need to wait some days to see how it adapts to the game?
Mega Metagross was OU in Gen 6 (and not much "Popular", but with Gen 7 and the terrains he was banned. What will happens here?
We can discuss all this questions and every single Pokemon in the council.
Of course for most of the experimented players this questions are easy to solve, but anyways deserve at least a discussion about it, and the council is the better way in my opinion.
I hope you consider the idea and could be implemented soon.
Thanks for your time!!!