All of these ideas are good, but I have a few tweaks I came up with myself to improve it.
1. Arena Selection Option: Let's keep it simple at: Every 30 minutes when they're swapping arenas, It brings up an arena selection option that everyone gets to choose which arena to vote for for 30 seconds. One with highest vote is chosen to be next. (Maps with the same number of votes require the system to randomly select one upon the ties.) To avoid constantly being the same map, you can't choose the map you're swapping out of.
2. Toggling team requests: I personally find this useless and could honestly have a negative effect. For the people that say, "It's so much easier!!!", It's really not. It doesn't take much effort to right click on a player. Negative effect: This could make the game much easier for coin grinding. The coin grinder can have 2 accounts (the one he wants to get coins on, and another account he wants to grind kills on). He could turn on autoaccept for the other player's account to constantly join matches. And get kills... and kills.... and kills.... Please comment if you agree with me or not.