To start off i would say that pvp coincil is a bad idea, in pokeone it clearly failed and in smoogon they have the best players in the world to do it (and even then, bans are still very discussed)
On pro it would only lead to more complaining, when the problem with balance in pvp is due to bugs and some key pokemons missing.
That said if you really have to make a pvp coincil things have to be done correctly.
1. How are council members picked?
How long can they stay on the council?
As much as they want to, only those who are able shuld be doing it.
What are the requirments?
Some people in this game only want a position that puts them above others, this people will do whatever is possible to gain that position, so it s a must for every memeber of the council to proove their knowlage about pvp.Only people that does good in pro turneys (winning and reaching semi-finals) and in ladder (reaching 80% with atleast 200 games played) shuld be allowed in pvp coincil.
Should they be able to participate in ranked PvP while being on the council?
Yes, doing pvp s the only way to have knowlage.
How would the split between Silver and Gold members look like?
This is irrelevant, this can work only if the most competent people are picked.
2.How are suspect tests decided?
How does the council decide what pokemon to send into a supect testing phase?
Not too many suspect tests have to take place, a pokemon is suspectable when it s uncompetitive, that doesn t mean a pokemon can' t be overpowered.A pokemon becomes uncompetitive when it has high usage, it has from very few to no awnsers according to their set, and requires from little to no prediction.Before sending a poke into testing council has to discuss about it s revelance in the meta, about it s sets and counters, only if the poke has the basis to be suspected the council will vote to start the suspect.
How would a suspect test look like?
People will be called to do atleast 50 wins with 80% win ratio in pro in order to express their opinion and the discussion would be opened in a thread on forums.
Who gets to vote after the suspect is over?
Players that meet the rquirments would.
3.What would council members need from staff in particular to make it successful?
How much influence does staff have over the council?
Council shuld be part of staff.
When can staff interfere in the decision making process?
Whenever the criteria to suspect a poke arn t met. When banning a pokemon in pvp it s important to consider the impact it has on the meta and how much it limits teambuilding.