I think the reflect damage with redirect mythic + dodge/block is a good idea. add arc dodge for more firepower. the problem with the idea is that with mana shield, it would need a lot of mana to buff the shield, + those 2 Talents. and a lot of all resist, as that will help your shield because of that one Talent. and mana regen/leach. a really tricky build.
you would have to put a lot of affixes into helping the shield, but if you take the shield out of the equation, the rest of the build would be easier to work with.