I'd also suggest attributes ratings, but additionally badges. So the badges could be weighted by their position (Bronze, Gold, Silver, HOF) and added to the entire score of the attributes to determine final position and grade. Some level of investigation would nevertheless be required to find out whether the 91 opal guy with 10 HOF badges is equal to the other 91 opal guy with NBA 2K MT Coins 10 HOF badges because one has Range Extender and the other has Ice In Veins (hint -- that the former is better). This segues into who should and should not get an opal. Many would agree that opals that are 281 is too much and undermines the integrity of this origin history.
Eddy Curry, Alex Caruso, Tacko Fall, Jonathan Isaac, Nicolas Batum, Jaren Jackson Jr. etc aren't titles your mom recognises. She knows who LeBron, Kobe, MJ and Shaq are. And guys like Walt Frazier, Jack Sikma, Dennis Johnson and Mel Daniels also deserve opals.
These are guys the young fan might not have heard of but SHOULD hear about because they were amazing in their period. And a part of this should be learning about the history of the NBA why bother licensing likeness and Earl Monroe's name? I'm not really sure when Earl won in 1973 many people who watched basketball are enjoying 2K. Even the largest NBA historian, Bill Simmons, just knows about a lot. Let's try to have some criteria when it comes to opals. Then they should happen to be 5 time All-Stars, if they're retired; dealer's choice, if they haven't. Kawhi and giannis have only been to 4 ASG's but we know more are coming and they deserve opals.
Same with Moments. Like he is doing in the Bubble, if a fringe man like TJ Warren goes, he should get an opal Moments card. He should not find an opal in a Flash package that is random else. According to the 5 rule for retirees, I'd also add that this would need to become post-1965. A man who left 8 teams once the league was only a couple teams and the contest was not the era's best due to prejudices, would not qualify for an opal. But the guys are in NBA 2K21 this year and all would have under my rule:
65 men got opals which never went to Buy 2K MT an All-Star Game and these were the most offensive (excluding the Players Club ones that were clearly useless, basically ingratiating themselves to present role players). However, the rest of these men are role players and could be hard-pressed to even be eligible for a diamond.