Mage Nuggets. Super easy to use, no config. needed, just drag bars around, resize if needed. Does bombs, invocation/rp, mana gems, cauterize, puts your portal spells on your minimap for easy access. It's a great add-on imo.
Tidy Plates/Threat Plates lets you show dots on enemy health plates for multidotting.
Having used most of the popular options (WeakAuras/PowerAuras, TellMeWhen, NeedToKnow) I've settled on TellMeWhen, I find it a lot easier to configure than any of the others and works really well within my UI. If you're interested I can export my Invocation and Mage Bomb strings for you to use.
I only have advice for bomb.. or rather ANY buff/debuff. OmniCC is the smallest, best addon ever.. never fails and I have been using it since vanilla. What it does is puts a big yellow number on your.. well everything from icons to buff to debuffs and you can make your debuffs bigger(not sure if this is OmniCC or Xperl though). I never lose my debuffs or miss a CD because of this mod.