Honestly, that might make the difference for me.
Oh, you smooth you!
Time to think out loud. Let's look at the mechanics for the race:
- It's a +2 Con +2 Wis, Medium race. This suggests a sturdy, serene look, rather than a whimsical, flexible look. They even have an ability called Hardy Form, which seems to hammer down this notion. More like tree bark than leaves and vines.
- Bonuses to Nature and Stealth. Nature is a given. Stealth gives us something to work with. They're sturdy, but can hide pretty well. Camouflage? Or maybe they don't fidget and move like animals, but can remain motionless like plants? This may add "cautious" to the "sturdy, serene" description.
- The 3 encounter powers are very un-plant-like. Ancients can be worked in through the old memories of trees, but Destroyer and Hunter? I'm seeing this race as embodiments of more than just plant life, but of the whole of nature. Maybe an amalgam of these aspects gave birth to the race? These certainly won't be mini-treants...
Let's run down a list of possible things to add to the race to make them look distinct from other races:
- No nose? As plant-creatures, perhaps they breathe through their leaves?
- Less digits? Dragonborn already have the 3 fingers + thumb hand. Maybe 2 fingers + thumb, like Nightcrawler?
- Root-like feet? Must look at 4e Dryad to avoid making it too much like them.
- Large eyes? Lateral eyes (like a herbivore)?
- Knotty elbows and knees?
- Thorny protusions on shoulders and forearms?
Color palette:
- Green is so obvious, I'm rather wanting to downplay it.
- Brown is good for bark tones, but there are many trees with grayish/white trunks, like beech, birch or white oak. The latter seems specially significant, being associated with strength and endurance in several cultures. Plus two Subgeneri of oak are called Quercus and Cerris, which could be good starting points for a racial name (Quercuns? Cerritians?).
- Yellow and Red. Several plants have colorful leaves, sometimes even if differenet shades running through a single leaf. Hmm... Green and Red might make a good contrast...
Avoid making the race look like:
- Swamp Thing
- Man-Thing
- Poison Ivy
- 4e Dryad
- Treebeard's cousins, twice removed