I am going to take your #1 and #4 together first.
I am suggesting that- LIKE PRESENTLY the SYSTEM determine a MINIMUM SALARY BASED ON SKILLS> This would not be random, but predetermined on same criteria for all players. IF people want to pay the player more salary, guarantee a longer contract (where salary increases over time starting at that base) signing bonus etc.
You mentioned that there would be min and max before. So using your #4
f yo udon't like signing bonus idea, it coudl be removed. Its an OPTION. The alternative to offering a signing bonus is higher pay or longer contract.
So basically whoever offers the max contract first get's the player. You know we can not implement more than one season contracts with current training system. Just because I could lock up my trainee for 5 seasons. If he starts at 5000 (have you seen any contract that doubles a player salary annually?), so giving him 10% raise a annualy for example (which is very generous compared to RL), we get a salary of 7320,5 when he is 23yo. He can be 100k+ player after 3 seasons already. Would create a lot of misunderstanding. Salary currently offers you a somewhat idea of the opponents strength.
About the number 2-s :
#2 NO this doesn't similuate completely real world contract.
I don't understand how salary range is better than fixed salary formulae? Currently the transfer list already regulates the different salarys per player/skill level. You might get the exact same skilled player for more or less, depending on the competition currently online/interested/funds available etc. Currently players and clubs are emotionless. They renew player salarys at the start of every season. Everyone get's offered a fair contract according to salary formulae. How is your system better?
In addition ending the contracts in the middle of the seasons with different contract lenghts will create a server heavy system. You will have to recalculate and update the player salarys during the season. How can that help the server load?
About buyouts. Guaranteed contracts are a pankrupcy favored system. If I relegate (yes I know it never happens in Japan unless you want to) I can't get rid of my high salary roster. How is that any good?
What I actually ment by buyouts is clauses that let you join a higher level club when the agreed sum is paid. A lot of contracts have these clauses. That's how I can empty my next cup opponents roster or remove the dangerous players.
If this is too complicated a concept for you, take an accounting course.
It has become clear, that you want a different game all together. Your suggestions are usually poinltess, seldom thought through and you seem to have never developed anything yourself + you like to rant, but do not put the work in to gather the facts (supporter coverage % comes to mind first). Perhaps you should stick to training basketball to girls.
There are ~50k managers in BB, most do not play in the top division, most do not know how to train effectivly.
So again, what is the upside of your proposed system?