MANY people have him at 7*... he can be good in epic in certain formations, but as the game is turning into "kill everyone in first 30 seconds" and because he is squishy, he is not used anymore in general. An awakening might make him usable again.
Sad that the tree dude is squishy. I don't have him yet so I couldn't comment on what awakening might help balance him, but if he's squishy, that might be something to fix. Maybe something along the lines of some physical damage reflection or a chance to intercept the healing abilities of an enemy or something like that would help his longevity. Maybe even ignoring damage below a certain threshold, including damage over time might help him be a niche defender, especially if he can ignore many summons, Sylphi ghosts and Ezio ultimates, etc. Yet still be afraid of single target killers or high-damage AOE. I dunno, just ideas.