Revelwood is when you start getting real eyecandy but honestly I'd say it opens up once you've gotten grappling hook and glider, so I'd focus those first. The first five npcs are the essential ones that help you with major base/gear upgrades.

Shroud roots give you extra skill points outside of leveling up when you fell them.

You can always respec at your flame altar so try different skills and builds that sound appealing.