How to Fix Arena; Pay Attention @Plarium
1) Add 3 more tiers to platinum and expand each one to allow more users
2) When players go "inactive" don't have them drop rank in the arena just remove them from the live system until they come back and when/if they come back they start at the bottom of the last rank they were in
3) Stop the weekly refresh/knock down and let the ratings be based on player win/loss (and team power of course)
This solves a handfull of problems and the biggest issue it would create is teams of people purposefully winning/losing against each other to "boost" ratings, but I'm sure we can figure out a creative solution to stop that if broadly speaking we fix the bigger issues causing folks to leave the community.
We need new players, we need new players to enjoy playing PVP against other new players, this really does need to be addressed if we want the game to last for years to come.