Hawthorne has had a much greater impact in my games than I initially thought he would. Turns out that AOE inspiration is pretty good.
On turn 1, I had all my units rally and Hawthorne used his inspiring words to give all the others a second inspiration token. This led to my oathsworn using moment of inspiration 3 turns in a row! It also worked well with my grayhaven channeler in that same game.
I feel like I seriously underestimated how much of a boost he is to most exhaustable upgrades.
Also, the upgrade that gives him +1 defense is great even without shield of margath and especially when you combine it with his white +1 defense modifier. 5 armor means that all the two threat units out there need at least 3 hits rolled to even scratch him.
This may have already been obvious to you guys, but he's really strong! I've been surprised at how effective he has been.