The newer colors are definitely better, they're still not perfect but they're better. Try adding like a purple or blue in as the colors get darker or something like that to just give the palette a little more flare. One thing that's really irritating me is the sloppiness of the outline, I can see this on Linn too, they outlines just look extremely jagged or misshaped. And lastly is, like Venetia said, it's too bland, there's nothing that makes it stand out. Add something else to it to make it look really awesome.
Here's something I did up really quick, it's not perfect but the outline's are a little smoother, I re-shaded it just a bit, changed the palette just a tad and the it's got some badass tentacles coming out of it's back xD
http://img125.imageshack.us/img125/3680 ... ampya2.png[/IMGZOOM]
The cool thing about this is that it's like an alien..you can pretty much do whatever you want with without people complaining about it being too unrealistic or anything. So use your imagination! Make this little monster something really awesome!