With level 39, I decided to finally bite the bullet and repec Aeven to be primarily 19/11 prot/ret. This allows her to keep +5% parry from Deflection, attack power from Improved Blessing of Might and added damage from the Seal of Command, all from the protection talent tree. Now, though, she also gets Divine Strength (+15% strength), Anticipation (+5% dodge), Improved Righteous Fury (-6% damage), Toughness, and Improved Devotion Aura from the protection tree.
We'll see how the shift in talents affects her leveling. Not much, I'd wager - she'll be harder to kill, sure, but there's a slight reduction in her damage as well, so mobs will have a longer time to try and kill her. We'll just have to see how that all pans out.
Long term plans: hit 40, get a faster mount. Hit 41, start queuing up for the two wings of the Scarlet Monastery that she hasn't seen yet. Hit 43 or so, and start thinking about venturing into Ulduman.