... that you smart peeps probably already knew about, but just in case.
I went on a quest to replace DoTimer. I ended up doing it with 2 add-ons replacing the one, but I'm much happier with the results.
CooldownButtons is small and simple. I can put my cooldowns on as many bars as I want, anyplace I want. So most of them are off where the old DoTimer ones were, but I've got Penance, PoM, and Holy Fire right above my castbar so I can quickly see the moment they go off cooldown (No Moz, no big button that tells me CoH is available ).
Satrina Buff Frames replaced some of what I was doing with both DoTimer and Pitbull. This is an OCD dream - you can define as many buff bars as you want, organize them how you want, and make any of those bars you want invisible unless you mouse over them. I could not stand that untidy mess of icons over my Pitbull frame. Now most of my buffs/debuffs display only when I ask for them, but for the ones I need to know about all the time I'm using Pitbull's Aura Bars (someone put up a screenshot of those here if you're not used to PB 4 yet). Nice and neat and square all the time. Shut UP I am NOT trying to make Pitbull look like Grid!