Salary, in my opinion, is not a good way to decide which players bring in more merchandise. Just look at Andrew Bynum. That guy has nearly $17M on his contract this year, but I don't think a lot of people are buying his jersey.
I believe many people did at the start of the season when most jerseys are sold.
I'd say it can be fine tuned by exceptional games, but game ratings are flawed depending on mins played.
And buzzer beaters are random and often occur during ridiculous circumstances.
What can regulate some extra merchandize is, if not salary itself, the salary growth. This will mean that it'll cost less for a team to keep a monster than for a new team to pay his salary. So people will wanna grow their own monsters, cause it's cheaper.
Because now it's either NT or bust, so it's a big risk to invest in training just to get unlucky and fall short, so many are discouraged.