Since your stats count mostly for different types of goals, I do not like any of these guys (Gilbert being the best out of the list). None of them are PIM heavy and they are all pass first, shoot later (or never) types of players (especially if they are on the PP).
That being said, I would hold on to Smith another week and see if his status changes. Keep in mind that he has had a very slow start and he is bound to bounce back. The opposite can be said for Diaz and Gilbert...
If you are really antsy to make a move, grab Gilbert. If you are patient (you may lose Smith for 5-6 games), I say hold on to the kid.
Keeper league 14 teams (H2H, 20 active players keep 16 NHLers, 16 minors)
Scoring Cats: G-A-PTS-PPG-PPA-(+/-)-HITS-BLK-SHP-SOG-FOW-GWG / W-L-SVS-SV%-GAA-SO
C- Crosby, Barzal, Bennett, Schmaltz, Novak
W- Forsberg, Batherson, Nichuskin, Tuch, Konecny, Maccelli, Sharangovich, Bertuzzi, Kaliyev, Neighbours, Reichel
D- Carlson, Rielly, Klingberg
G- Hellebuyck, Demko, Merzlikins, Vejmelka
Minors:
F: Fantilli, Cooley, Bourgault, Perreault, Cowan, Ohgren, N. Foote, Goyette, Iskhakov, Denisenko, Tracey
D: Simashev, Willander, Lambos
G: Schmidt, Rodrigue, DiPietro, Gaudreau, McKay