Brad Smith can play WR, QB and KR but doesn't do any of them well. The guy is completely worthless, it has nothing to do with misuse.
I look around the league at what passes for a backup QB, and I think Fitz is better than a majority of those guys. Absolutely no harm in keeping him around strictly as the #2.
And Wilson may not be perfect, but who's gonna play strong safety? Add it to the long list of needs?