The prospects in LHV right now are better served playing a lot of minutes in the AHL.
Foerster for example probably needs a summer to work on his skating and improve his puck handling, if he struggles a bit in the AHL, he'll be eaten alive in the NHL.
Only a handful of NHL players are ready at 19-20 years old, and they tend to be top 15 picks.
Most don't start until they're 22-24 years old, with D-man generally a year or so older than forwards, especially D-men who lack top skating skills (b/c they need the experience to avoid mistakes they can't outskate).