No. "Negiligible felony" and "felony" will incite the same quibble. The point is having a history as a felon, period.
I'm dodging the question because you should be focused on the "shady" characteristic. Even a morally reprehensible felon can appear non-shady. And a "shady" person with "negiligible" felony probably overly skews or augments their own perception of it, which makes them appear even "shadier" than they would without the felony, whatever its stripe.
Whatever the case, "felony", whatever its qualification, has a legal (non-personal) meaning, and it only has a meaning in that sense. Look at GEM Anscombe's distiction of institutional and brute facts. There's no such thing as a "brute fact" of felony.