I like many of the redesign choices you made. This definitely will be a wordy response, since I feel like saying a lot. There are two things that I especially want to go into (there is a TL;DR if you want the main points).
First, I like how you redesigned the face, removing the strand of hair covering the face, bringing out the ears and the fur on the side, separating and bringing out Rillaboom's eyebrows, and reshaping the mouth to be less square compared to the original. I'm getting both monkey and a bit of bear from the overall face, and a lot more power (you mentioned you wanted to bring out the savage look).
Second, adding the twigs and reshaping the leafy hair to be more pointy gives the overall design great movement and increased size. It's especially prominent on the back, as if the fur on Rillaboom was spiking outwards like a porcupine (again, adding to the power of the design). It also fits the idea of Rillaboom, maybe sticking the sticks onto itself as a defense and to use as weapons later.
I like the addition of the light green as an accent color to the overall design, especially Rillaboom's eyes. However, the extra light green tuffs on the head and chest feel distracting and don't feel like they fit in with what's around them.
While I'm not 100% with the original, the green hair tuff in the original feels like it's extending out in space due how it comes out from the eyebrows in a V shape, how flat the back fur is around the tuff, and its color. The tuff in this redesign is a much brighter color compared to the back fur. There's already some great volume coming from making the leaves more pointy. The 3D look of the green leaves contrast with how flat the light green tuff feels, how it sticks straight to the right and how there's no shadow on the bottom of it to give it some form.
The design could get away with removing the light green tuffs but leaving the light green in the eyes to draw attention to the face. Maybe there's another way to add the light green, but I'm too lazy to come up with ideas at the moment.
Thanks for reading this. Most of this is nit picky for something that supposed to be fun, but I just really like character designing and talking about it.
(TL;DR) I like your design over the original. Two great changes gives the design more power; don't like the light green tuffs.