I do not feel you need to rent a player to overcome veteran teams.
high salaries in playoffs make winning teams go red, which sucks, but if we are always green- then no one coudl ever catch you.
You would not be always green. Currently you might be green even with near 900k roster (if you negate staff and scouting). Perhaps you could even maintain higher player salarys if you got a lot of self drafted/NT players. I think it would be a good thing for the competition, if teams that go over the average total earned by teams in the league, with player salarys only, to burn out faster than before. This also limits the gains of tanking, relegating and overspending to get back up. Additional player salary tax would eat all that cash you got while tanking.
I also don't think that teams in the big countrys have hoarded up all that money 15 seasons ago and would never use it to win.
Estonia for example has had 6 different league winners and 7 different cup winners, last 10 seasons.