The construction isn't all that "messy" pace Van Eynde et al.
It is saying that something, an instance of class X, is not likely to be less [adjective] than any other instance of class X, under the said circumstances. In making a comparative predication about an example of a class relative to the rest of the class, it is simply not amenable to a plural comparand. If you need to use a plural, that is, if you need to compare several things to the rest of the class, must supply a singular collective noun that groups them (as you suggest), but that isn't always easy to do. And that's not a limitation of the language, as you would need to have a basis for comparing them as a subset against the other members of the class, and that basis doesn't always map neatly to a collective noun.
It is as good a car as you can hope to find in your price range.
These are as good a couple of cars as you can hope to find in your price range.
He is as fast a runner as one can be whose legs differ greatly in length.
They are as fast a track team as you will find, where each of its members has legs that differ greatly in length.
As an alternative you can use each with a plural noun:
Each of these cars is as good a car as you can hope to find in your price range.
Each of these runners is as fast a runner as one can be whose legs differ greatly in length.