Heal is useless since you will be having 40k+ hp and only being able to heal for ~2k.
The only time I ever thought Earth Drive was viable for leveling was when reflect leveling was still big, it was extra chip damage to help clear off mobs a tad bit faster...
Also, I don't see the point of maxing shield reflect... too situational, and 5 skill points spent better elsewhere.
Max Cavalier Mastery....
Defending Aura maxes at 5
For leveling, full shield is useless, unless you just plan on going to share parties/TI parties all the way to 150. Which really, doesn't matter what skills you take as long as you know how to mob.
End game, a full shield build will only be used for supporting. And even then, skills like Shield Press aren't quite useful.