An addon that would show the cooldown on Arena Gladiators Proof and Siege of Cyrodiil Merit would be awesome!
The Arena Gladiator Proof is gained by completing dailies in cyrodiil and the Siege Merit by completing dailies in Imperial City. If you are on cooldown you "waste" daily rewards.
Surprised WPamA doesnt handle this, it might do, I only use it for Dungeon/Trials. It has timers for trials, randoms, and some pvp stuff in it. Put in a request on WPamA, the author has a healthy obsession with all things timers .