I think that barearmed gorilla is looking very good, I also like the lynx ear, they blend more with the design than those cat ears...the hero is looking pretty good now.
the cat ears and the gun sort of clash though, the gun's paintjob together with the wires on the back and the cat ears make that whole area look a little too crowded. I think the yellow/black wires call too much attention and are thematically less important because they are just MORE of the character's cyborg features, while the Lynx ears are the only hint that the gorilla's genetically modified, therefore far more important. You need to take the focus away from the wires (I'd remove them) and make those ears stand out a little better, they get lost on top of the gun.
Also, I cant see the gorilla's face you need to make it more caricutarized, or give him some cool glasses like those toys you referenced.
This is is an aspect of pixelart that you should keep in mind "design 4 size", you're designing for the final aspect ratio that things will be shown in, so you should put only the details that can be shown in your intented resolution, not less not more.
The animation lokos pretty good, it just lacks analysis of refferences. I really think you're understimating how you can make your own design a lot better if you refference real life and draw your own caricatures, rather than try to do what others have done.
Look at this gorilla walking from the back
http://www.youtube.com/watch?v=8afAqnar3qw&feature=related check this after 2:02
Gorillas dont walk straight, one leg goes in between the arms, the other goes to a side. They are in a spot between pibed and cuadruped that's why their walk is flawed.
their whole walk is them putting their arms forward, pushing down...then swinging their body diagonally to avance. You should incorporate some way for your guy to move his shoulders, there's a LOT of that oll over a gorilla's motions
http://www.youtube.com/watch?v=HDxA8-01cp4&feature=relatedthey throw their arm forwars with a lot of force, and then they tense them to push their torso and legs off the ground..(this is the point where they're highest in their walk and you sorta diluted it) then they swing to a side and fall.
Your walk right now kind of assumes that the tiny legs are powering it as much as the huge arms do, which obviously cant be so it looks floaty and sort of unnatural.