Interesting thought! I make intensely thematic armies and lists, so I hadn’t even considered it
On the whole I’ve been happier with the Forest Shamblers than I expected I would be - they’re extremely generic elementals, but thus far that De5+, At18, CS1 base has done more work than I thought it would. Maybe that shows how pillow fisted most of the army is 
Speaking of rethinking unit roles, I’ll spoil the list I’m playing next:
Forest Shamblers Horde
Forest Shamblers Horde
Forest Shamblers Horde
Tribal Spears Regiment
Tribal Spears Regiment
Tribal Spears Regiment
Tribal Spears Regiment
Centaur Bray Striders Troop
Centaur Bray Striders Troop
Beast of Nature - Upgrade with Wings, Increase Attacks to 7
Tree Herder - Trickster’s Wand, Surge (8)
Tree Herder - Surge (8)
Centaur Chief - Blade of Slashing
Druid - Conjurer’s Staff, Bane Chant (2), Heal (2)
Total Unit Strength: 26
Total Units: 14
Target Points: 2300
My games showed that the Spirit Walkers aren’t really fast enough to project real threat, and De3+ is too weak (and 165 too expensive) to perform the utility roles I want these regiments to do. Tribal Spears wildly improve on that survivability for significantly fewer points, but with enough attaks to let me roll a decent amount of dice and make lucky flanks a thing.
Swapping all four regiments over gave me enough points to upgrade the Warden to a true hammer, which I’m going back to the Beast for that raw utility. I have a Minotaur Chariot regiment that could serve here, but I really should learn how to run a flying monster at some point 
Finally, I’ve concluded what most people do in regards to the Great Chieftain, that the Centaur Chief is better at flyer interception, blocking, etc.