1x Paladin 1x Disc\Holy Priest 3x Warlocks ? Your thoughts on this please.

Greetings all. I've been leveling up 4 Warlocks and 1 Disc\Holy priest and recently decided I wanted to replace a Paladin with a Warlock. Right now I'm playing the Priest as my main class and backgrounding the other 4 Warlocks. Every instance this far has gone easily (I'm at 44). Now - if I want to put in a Paladin I'm guessing I need to play the Paladin as the main and sub the Priest. Which addons and macros would you suggest to make this easier? Right now I'm using Voidwalkers to pull massive mobs and aoe them down with Hellfire and Holy Nova(Imp. Holy Nova glyph.)
Thanks in advance for your advice and thoughts.

Spec your locks destruction or demo for the felguard (at level 50)

1) Insta pull with pally using Avenger's Shield (not assigned to a keyboard button, just a clickable button on your pally screen)

2) When the mobs reach your pally, hit your "universal pally attack button" a couple of times (macroed as "/castsequence Hammer of the Righteous, Consecrate, Holy Shield")

3) Hit your AOE attack/pet attack buttons till everything is dead

4) Repeat till level 70

The above is good for instances or group pulls, but you might want a smite/shadowbolt attack button for single mobs - should go much faster killing singles at range.