Ya, that's a pretty tough one. You're talking about 3 guys with pretty similarly solid upside. But, I think Brunner has the most. I've watched him pretty close for the 1st 3 games, and he looks like the real deal. You can tell he's still getting used to the rink size and the overall feel of the NHL, but he has a shot at being a difference maker on a fantasy roster.
I would cut Okposo just by default. I actually like him, as well. But, out of Schenn, Brunner, and Okposo in a keeper league he's the odd man out.
Tough call, though. But, I think Brunner is worth a roll of the dice.
20 Team $$ Dynasty League (23 man roster, 27 man minor roster) w/Salary Cap at $80M on Fantrax **1 Time Champ
G, A, P, +/-, PP, SHP, Hits, Blocks, Wins, Save%, SV, GAA. *1 goalie starts
C - Couture, Kadri, Anisimov, Dvorak
LW - Marchand, JT Miller, Grabner, Hartman, Duclair
RW - Duchene, Oshie, Silfverberg, J.Williams
D - Ristolainen, S.Jones, Martinez, De Haan, Del Zotto, Chychrun, Carlo
G - Lundqvist, F.Andersen, Raanta
Minors - Meier, Barbashev, Barber, F.Perron, Heinen, Cholowski, T.Motte, Quenneville, Beaudin, Novak, Sissons, V.Dunn, Lauzon, Hogberg