No question. Stepan is the best option out of all the options you have listed. Berglund definitely has some upside, but it looks like Stepan will have more opportunity to have a better year. If he continues to get 1st PP time, which he should, it will end up being a one-sided comparison. That PP unit is gonna be ridiculous before it's all said and done.
Desharnais is intiguing, but I'd still rather have Stepan.
20 Team $$ Dynasty League (23 man roster, 22 man minor roster) w/Salary Cap at $75M on Fantrax **Defending Champ**
G, A, P, +/-, PP, SHP, Hits, Blocks, Wins, Save%, SV, GAA
C - Getzlaf, Eakin, Eller, Ott
LW - Eriksson, Marchand, Bailey, Zuccarello, Malone
RW - Perry, Vrbata, Pavelski, Bennett, Etem
D - McDonagh, Markov, Gudbrandson, Seidenberg, Visnovsky, Gunnarsson, Vatanen
G - M.Smith, C.Anderson
Minors - Horvat, Spooner, Reinhart, D.Leblanc, JT Miller, Jankowski, S.Griffith, Dauphin, Havlat, Ceci, Merrill, Tennyson, Zidlicky, Gilbert, Bartkowski, Greiss, Visentin, Binnington, C.Johnson