@krakowitz
The NBA has a salary cap, just like the NHL does. Players leaving to form "super teams" are because of the way that the salary cap is structured in the NBA (luxury tax, guaranteed contracts, buyouts, etc.) The NBA is also a growing market. The NBA has also less luck involved with the game compared to the NHL (one player cannot take over a hockey game vs. running isolations and post ups).
The Miami Marlines didn't sell their players for less than market value because they couldn't afford them. Mike Stanton said he would go to four teams and the Marlines Ownership took the best deal - it happened to not include elite level prospects. The trade of Christian Yelich was fine, as the Brewers knew that the Marlines wanted to move him, lowering his market value.
In my scenario, there would be a luxury tax in which a team has to pay "x" for every "x" they go over - say teams have to pay a five to one ratio for every dollar spend over the luxury tax (in terms of cap hit). Sure, you may have been able to keep Marcus Johansson, but it would have meant that the team would have had to pay a set ratio in order to keep him under my model.
Owners will not spend whatever money is necessary - it would completely depend on the market. They are all rational economic actors and will not spend an asinine amount of money on players if there is a strong enough economic disincentive.
Again, your taking a model in the MLB or NBA and applying it to the NHL. There would be a minimal lack of parity between the two teams, especially if you combine both of my ideas together.