In English the only (mildly) derogatory words I know of for having no other faults except being too good are Choir Boy and Boy Scout.
In both cases these refer to someone who is either uncompromisingly good in a way that others find either constricting or even oppressive, or alternatively, someone who is so good that you cannot act (or speak) normally, you are compelled to act better around them to conform to their expectations which are proper, so you cannot reasonably argue against them.
In English, you usually use some emphasizing qualifier to indicate that you are using the terms derisively, as in "Joe's such a choir boy.", or "Not with a real boy scout like him." Note that the derision implied is very mild and usually carries a hint of admiration as well.
Example: In DC Comics, the always good-guy Superman is sometimes referred to as "the Big Blue Boy Scout", by criminals and even, on at least one occasion, Batman.
And though I have never heard it, I believe that you could also use either "Choir Girl" or "Girl Scout" in the same way to refer to a female and most hearing it should understand the allusion.