OK, lets go:
1- To get in deep with the keys: can you specify more the way of getting them? Will be mandatory be on a premade team to get them, or that will only raise the positibilities?
2- Only 4 chests per month? Does that mean that for exemple, I get a chest for getting a +S with Sona and Veigar. Then i was playing Hecarim and Ahri, though I have no mastery level with them, my teammates get an S and I win two chests with both.
Is this scenario plausible? If I understand it correctly, I can't win another chest until next month and I can't win another chest with Sona, Veigar, Hecarim and Ahri until the next season. That's correct?
3- Can you put examples on the quantity of essences we will get from the chests? What's the minimum / maximum?
4- Is there a limit of how many chests /keys can you buy with RP? Have you considered making them available with IP?
5- Will chromas be part of the chests' loot in the near future?
6- Related to the mastery of champions, when will we be able to get points from another gamemodes? ARAM, TT and Dominion?