Salary Cap: Minor, but .738666667% should be 73.866666%.
Trade Limits: I would suggest there be less trades per month (3?), an additional 4 trades in the 2 weeks prior to the trade deadline (2/week), and probably double the off-season trade limit, especially if it includes draft pick trades. Those are typically busier times for transactions and restructuring teams and the times when you would be able to use those extra trades for picks/minor league transactions. For the current pre-season, GM's are going to want to make some kind of an impact on their rosters before the season begins. So maybe the off-season 5 works for a start and then the next off-season can have the 10 limit.
NMC/NTC: NMC's can only be waived if the IRL counterpart actually waives it. Anything else is just speculation. Aside from the expansion draft, which was a special case, there are very few reasons for a player to waive an NMC. He is basically saying he either wants to be buried in the minors or claimed off waivers. That doesn't happen very often. A player would rather force a team to buy him out.
Retained Salaries and Buyouts: I'd like to see a restriction or evaluation process for retention as well. I've seen too many retained salaries that just aren't reasonable. Like 50% on quality players or players on long contracts. The goal is to bring their salaries more in line with their performance, not make them into bargain price players.
Trades (35%) Lowest score total (1-5) scale: I don't think forcing a team to make 12 trades is a fair evaluation tool and is counter-intuitive. An astute GM may not need to make 12 trades. If anything, they will make a few really good trades and then a bunch of nothing/junk trades just to meet the requirement, thus devaluing the few good trades they did make.
I
think those are the only issues/considerations I can see. Other than that it looks pretty good.