I don't think the Speckled's green mane is lazy-- I think it sets off the speckly bits quite nicely, and doesn't do things to the eyes. Speckled, like Glowing, never seems to be an adventurous colour (don't know why), but I don't think this one's a bad job for what it is. Mind you, I speak as a non-Yurble owner.
Desert is interesting. I know the base colour looks like yellow on its own, but it's definitely different from the
Yellow Yurble, and I like it better. Less brash, although Yurbles aren't generally subtle beasties. I'm a little puzzled as to where the mane is being kept-- under his hat maybe? I'll be interested to see if he's bald with the hat off. Also, how come he's got dark paw-pads on his forepaws like the ones on most Yurbles' hindpaws? Deliberate, do you think, or miscommunication somewhere along the line?