LDS was in a very nice way stating the obvious. He is pretty, but has obvious feathers showing that makes most taxidermists cringe. In other words that bird will most certainly be less than perfect. Look near his shoulders and scapulars, and you'll see those feathers indicating problematic areas. My guess he won't have as many pinfeathers, as undeveloped feathers. It looks like a first year bird versus a bird coming out of molt, because those feathers that are similar to a hen's feathers, are also found on juvenile birds. Juvenile birds (or first year birds) actually tend to be prettier than an older bird, at least concerning early season birds, due to the fact they don't molt like a mature bird does.
Can it be mounted? Certainly. If it's your first bird looking that nice, and is special to you, then by all means, have it mounted. In my opinion, a flying bird would be best for a bird without perfect plumage.