That's an American Dragon: Jake Long reference in the name, isn't it? The art is very pleasant through its coloring, texturing, and pose.
Normally, scales on a mammaloid would require some explanation, but the lineage does have a long history of scales and scale-like spikes. The ancestor of its ancestor had scales on its belly, after all, and the Longjack also had subtler, pebbly scales on its belly. I recommend mentioning the long history of scales, spikes and scutes in Lutrasoricidae/tamjacks, and how its small body scales are simply an expansion of its ancestor's belly-scales.
It is very large. It might be useful to mention how much of its length is its tail.
Does it retain any vestige of its pouch?
Do its young have any predators? I figure Seashrogs and Wolvershrogs are some candidates. Great Leotams hunted its ancestor, but they don't seem to have overlapping habitats anymore.