In your league I wouldn't want to have a D as a prospect. With G and A as the only skaters cats, D's don't have too much value. Every season there's at least one surprising D popping up who can be had for free, so no need to wait for one until he has developped as hoped. What I'm saying is that I'd drop Ellis in a heartbeat for one of the top fwd prospects available. Personally I'd go with Tarasenko and I'd also consider to drop Kreider for one of the others.

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12 team H2H dynasty
G, A, +/-, PIM, PPP, SHP, SOG, FW, HIT
W, GAA, SV*, SV%, SHO
C,C,C,LW,LW,RW,RW,W,D,D,D,D,Util,Util,4xBN,2xInf

Team:
C: Stamkos, Tavares, Kopitar, Hanzal, Legwand
C/RW: Backes, Pavelski
LW: Lucic, Landeskog
LW/RW: Lupul
RW: Clarkson, Hornqvist
RW/D: Byfuglien, Burns
D: Letang, Streit
G: Smith, Bryzgalov, Hiller, Fasth
IR: Kovalchuk

Farm:
S.Bärtschi, M.Foligno, E.Kuznetsov, J.Morrow, N.Niederreiter, T.Tatar