This second variant is capable of performing some really nice tricks. The 10 healing surges as a base are a definite must, since Con is onl the tertiary stat for Abjurers, meaning they will likely start with something like 10 Surges after apllying Con in Quickleaf`s variant and that`s simply too few for a proper defender. So if I may suggest, grant your abjurer another healing surge, Quickleaf, I highly doubt it is going to have any negative impact on game-balance. A defender that`s sucked out of healing surges after two or three encounters would slow trhe game down too much.
Taking a quick glance at K`Zach`s build three things came to my attention: Continuance is a potential gamebreaker in Solo/Elite encounters. Forbiding saving throws is a big "NO, NO" in 4E. Abilities like this truly have the potential of shutting a solo down. There are too many ways to abuse this power to create the dreaded 'Solo-stunlock' Combine the Abjurer with an Orbizard and watch your parties wreck your solos in no time.
Dispellation is another very strong power, but I would have to see it in action at my gaming table to determine whether to nerf it or not.
I`m not sure about Avoidance, -4 to attack sounds too harsh but then again it only affects the next attack roll against a chosen target. If I were you, I`d probably change the power a bit to sth. like this:
Avoidance
Standard Action Implement
Intelligence vs Fortitude
Hit: The target takes a -2 penalty to all attack rolls against an ally of your choice until the start of your next turn.The first time the target attacks the chosen ally before the start of your next turn, you can make a ranged basic attack against the triggering enemy as a free action with a bonus to the damage roll equal to your charisma-modifier.
This way you still get some effect against multi-attacking monsters and the monster truly has a motivation to leave your ally in peace. Attacks like Avoidance IME only get used when the need is dire( a bloodied leader the monster could finish off with a single attack or sth. like this) and in a situation like the one i just created most monsters would stick to their target despite a mere penalty to attack rolls.
I`ll give you a more elaborate feedback once I`ve had the time to check these two builds more thoroughly.