Most lower round picks are long-shots from the moment they are drafted. It's the exceptional ones that develop into players that can alter a franchise's success. Even the small percentage that do carve out an NHL career tend to be more at the lower end of the roster, and there are many ways to acquire that level of player without draft and development.
My view has shifted somewhat, so that I don't think it's all that important to draft and develop prospects that end up in the bottom of the line-up because they are easily available for low cost, and you can actually then acquire players that fit particular needs / roles at the bottom of a roster. Instead, I really think it's quality over quantity of prospects. That usually means picking in the first couple of rounds and hoping to hit a few home runs from those types of picks. Generally, the Jets have done well with their 1st round picks, and until recently they haven't been all that good in the 2nd round. However, Salomonsson and Lambert look like they might be 2nd round / late 1st round picks that can transcend their draft position and become impact players (jury is still out, though).
If Samberg transitions to a good 2nd pair D, he's another option. They have to hope that one of their other higher picks like Perfetti, Barlow, Freij or Lucius develop into top-of-the-lineup difference-makers, but the odds are long.
McGroarty needs to be converted into a prospect or young player or pick that can be a difference maker at the top of the F or D roster.
Lately, the Jets' success has been driven more by some good trades by Chevy, moreso than draft hits. That's helped them to remain competitive, but they really need to nail some draft picks, and hope that some of their drafted players take a leap forward in the next year or two. That's how Dallas has leaped forward, with Hintz, Oettinger, Robertson, Johnston and Stankoven.