If it hasn't been said, I need to explain some game mechanics which might dent your initial solution for PBAoEing mass mobs:
In EQ, the XP was given to the group which did the majority of the damage. If Group A did 51% damage and Group B did 49%, Group A would be rewarded all the experience and loot rights. Likewise, if Group A did 49% damage, and a single non-grouped char (EI a high level) did 51% damage, the single char would be awarded all the XP and loot rights. This was the birth of the KSing QQs (one group would steal a kill from another group that pulled a rare by outdamaging them).
In WoW, the first person or group that deals damage in any form to a mob (hit, spell, damage shield) has "Tapped" the mob, and will receive loot rights no matter what. For the group to receive all XP from the kill, they must outdamage other groups/chars by 50% of the mobs health. If they do not to at least 50% damage, they receive a portion of the XP scaling downward from 100% - 0% based on what portion of 50% of the mobs health they took away.
I bring this to your attention for the following reasons:
Your rested group, which is meant to get the XP, will have to pull and tap each mob.
No mage early on can survive pulling more then a few mobs at a time. You heal the mage, and all the mobs go after your priest/healer.
Mobs only chase chars a certain distance before agro resets to nothing and they "Leash" back to where they were agroed, or where they spawned. This would prevent you from amassing any significant size of pull.
Masses of world mobs is much smaller then that of EQ. I remember AoEing some outdoor Iksar fortress in some lvl 30-40 zone with a lake which had about 100 mobs inside, all bunched together relatively tightly, and being able to pull almost the whole thing with my bard. Nothing like those areas in WoW.
I'm not saying it is doable, but I really believe that you will have far more success doing the following to level your teams:
Create a single Paladin and level it up to 70 OR Create a 5-man group of Paladin, 3 mages, priest (because you want to end up with 24 mages + priest) and...
Get the Paladin + group to 70 asap.
Lvl Mining and Jewelcrafting on the Paladin.
Create Figurine of the Collosus, for use with the Paladin.
Buy or make gear for Paladin for tanking purposes.
Use the Paladin to AE your next 4 mage group through instances, using the many Paladin Boosting guides out there.
When each of these mage groups reaches 60, consider trying out the Paladin + 4 mage or Priest + 4 mage to see what works better for you in instances. Grind out instances to reach 70.
Repeat this for each of your sets of mages.
You may want to try to PBAoE the whole group to 70, but this depends on what your goal in this endeavor is: Leveling 25 chars at once, or playing end-game with 25 chars. Personally, I would skip all the crap in between, as with 25 chars you will be missing a vast majority of the content as is, and beyong content, there isn't much else between 1 and 70.
At least leveling the first group I mentioned you would get to see all pre-70 instance content (or whichever you choose to see, you have the ability to see it all), and, in my opinion, end up reaching 70 with all 24 mages faster then if you were to PBAoE them the whole way.
Good luck to you.
