Pretty much the whole point of your post is the point of the draft is to acquire players you wouldn't otherwise be able to add through free agency. But that seems to suggest the best draft strategy is to swing for the fences through all 7 rounds, which if you ask me is a terrible way to draft.
You end up having a boatload of late round picks who essentially are on the level of not being up to snuff for the AHL and a boatload who are going to flop in the the AHL. Essentially, you sit waiting to turn one pick every couple years into a player at the NHL level while entirely relying on overpaying on the FA market to re-stock your lineup. Generally you'll have minimal depth into the minors for injuries and a farm team that isn't competitive.
Not to mention a lot of these guys STILL don't pan out anyways. Kadri from being a blue-chip high potential pick has become a 2nd/3rd line centre. Pretty much, the longer you follow prospects the more you come to realize how often and how much even the most promising prospects tend to fall short of their perceived potential.
Long and short of it is the swing and miss strategy on high-potential boom and bust players is great in a EA Sports environment but it simply isn't sustainable. An organization needs depth and realistically as you get into later rounds when the liklihood of getting an NHL player is greatly diminished, just pulling an NHL player is a huge advantage. Having a constant influx of cheap cost effective players who are waiver eligible who play in the minors is a huge advantage. Having 3rd and 4th liners who haven't hit their UFA years and are cheap is a huge advantage. Having a competitive farm team for players to develop in is also a huge advantage.
So pretty much, no, drafting is reliant on hitting and producing NHL players.
Seems to me that its super easy to acquire these guys via free agency. Panik, Matthias, Winnik, Raymond, Santorelli, Smith, Booth, Paranteau, Arcobello, Hunwick, Brennan, Abbott, Froese, Mikkelson, Bodie, Hamilton, Aucoin, Zigomanis, Kostka, Smithson, Bailey, Erixon, Hyman.
These guys are all examples of guys that were acquired for nothing over the past couple years and are either solid 3rd/4th line players or who have helped make the Marlies a more competitive team.