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) PPP (15) SHP (25) OTG (15) GWG (25) HTr (50) SOW (75) HIT (1) BLK (2) W (50) SHO (100) OTL (10) GA (-15) SV (2) Use actual NHL salary
Start 12 F, 6 D, 1G weekly
F: Kucherov, Marchand, Barkov, Gaudreau, Laine, Aho, Dubois, Dadonov, Huberdeau, Trocheck, Bertuzzi, Beauvillier, Khaira, Grigorenko
D: Ekman-Larsson, Yandle, Edler, Pulock, Borowiecki, Weegar, Mike Reilly
G: Andersen, Hart
Farm: Boldy, Beckman, Wise, Mascherin, Kovalenko, Manukyan, Walker, Morozov, Shafigullin, Palmu, Tychonic, Zhuravlyov, Kesselring, Zamula, Lankinen, Sogaard, Ingram, Rybar