If we look at this from the perspective of upside/contract/asset cost for everyone except Hellebuyck:
Campbell
Upside: Could be amazing and be good enough to get it done, could be a total liability like he was this year as well. Has had just as polarizing of a playoff run. Still very unproven, and he is 30+ now.
Contract: Very likely to be overpaid, because he is at best a 4-4.5 mill on a 2 or 3 year deal. If a team wants to give him more term or a 5+ mill contract, the upside is simply not there.
Asset Cost: Zero, which is ideal.
Varlamov
Upside: He is older, but he knows how to be a starter, and has had playoff success with iffy Islander teams. Will probably need a strong backup to split the net with him just so he doesn't get worn down, but the combination of risk vs. upside is probably no worse than anyone not named Hellebuyck.
Contract: Only one year left at 5 mill. We could swing it, but we'd need to move Mrazek (possibly to the Islanders themselves).
Asset Cost: That along with his NTC may be the most prohibitive part. He should not cost premium assets, even if money like Mrazek goes the other way.
Kuemper
Upside: He got it done, but he is 32. Can he do it again? He has been very up-and-down in Colorado. He wasn't exactly a guy who dominated.
Contract: Probably more than we can afford and more than he is worth.
Asset Cost: Nothing.
Gibson
Upside: Who knows. Is he going to continue to be subpar. Is he going to return to top form. Somewhere in between?
Contract: 4th highest paid goalie in the league with 5 years left. It is not a matter of 'if' but how much money Anaheim has to take back, because nobody who wants him can afford the contract and he is a negative asset at the full price. Even then, for the amount of risk involved, it will give a lot of teams pause.
Asset Cost: Depends on how much money Anaheim is taking back, but even then, I don't see teams throwing huge assets at a guy who has struggled like he has.
Fleury
Upside: He is old, but he is Fleury. Does he have enough in the tank for another run? Will we need a strong backup?
Contract: Given his age, he shouldn't be demanding huge money. He is likely looking for "fit" more than money anyways. That fit is likely the biggest thing that could prevent us from getting him.
Asset Cost: Zero.
Husso
Upside: He is unproven, but has a recent history for success and is still fairly young. He is the kind of guy who could get things done.
Contract: Should be reasonable, but who knows if someone will overpay for him.
Asset Cost: Zero.
Blackwood/Samsonov
Upside: Young and prestigious with that upside, but both have hit rough patches. Will be important for a strong goalie department, but Mrazek could be a good partner for either.
Contract: Lowest out of the bunch by far. We can probably afford to keep Mrazek around at their cap hits.
Asset Cost: Probably nothing much. Maybe a B-prospect and something small.
Out of all of those risks, a young guy like Husso/Blackwood/Samsonov could form a strong tandem with Mrazek next year (or someone else if the right deal is there). With a strong team and a hopefully high caliber goalie coach working with them, maybe that is the type of swing which connects for a Cup?
Then you have guys who are more proven, but higher cap hit and greater risk of getting worn down.
I think it is pretty clear that Gibson should be at the bottom of the list right now though. Terrible contract. Possibly the highest asset cost. And even the upside is iffy.