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.