I would take a page from a WoW addon. SCT cooldowns allows you to setup your abilities such that they will flash on your screen when they come off CD. An option to turn this on or off would be great, since you can see what has finished cooldown without having to look at your ability bar.
Another option is to do something with your unit frame that shows health/mana. Maybe have 4 green dots or blue dots that turn black or red when the respective ability is on CD. so if my ult is down, button 4 is a different color.
Also, a hover chat bubble above the champion is necessary. Current chat seems buried in the corner of the game, and if i could get the last 3 team chat messages above my toon at all times, i could easily see gank calls, mia's and retreat calls.