I think you're undervaluing Strome here, although it seems like the rest of your league is, as well. I have no problem with you moving Strome to focus more on a 3 year window, but if you move him I feel like it needs to be for something more than Hamonic who's a solid player but Strome is a top end prospect.
If Hamonic is the best offer you're getting for Strome atm, I would hold onto him and wait. Someone will give you a better deal eventually, and if they don't no biggie you keep a very good prospect on your roster for the time being. There will be a boost to his trade value next summer when it's determined he'll be skating with the Isles.
20 Team Dynasty (points per) - G (25, 50 for defense) A (25) PIM (3) +/- (5) PPG (15) SHG (25) OTG (15) GWG (25) HTr (50) SOW (75) HIT (1) BLK (2) Use actual NHL salary
F: Malkin, Tavares, P. Kane, Neal, Nash, Okposo, Moulson, Ott, Whitney, Iginla, Pouliot, Garbutt, M. Martin, Stajan, Raffl, Klinkhammer, Clune
D: Green, Ekman-Larsson, Bogosian, Gudas, Stone, Oduya, Ranger
G: Anderson, Lehner
Farm: Grimaldi, Gaudreau, Hurley, Hartikainen, Stransky, Fast, Tarasov, Petrov, Kosov, Kujawinski, Maidens, Nurse, Ceci, Donovan, Ekholm, Thrower, Kichton, Borowiecki, Marchenko, Poulin, Nilsson, Andersen