I'm also fine with eliminating the non-playoff team bonus of +3.
As far as eliminating warehousing of players, I feel the 20 game played rule to be eligible for the playoffs is a great idea. But if owners are still warehousing players, the only way around that may be to increase a players salary every year regardless of how many games they have or have not played. Once the player is drafted, the clock starts ticking on his salary. You will probably have to increase eligible seasons by at least one year though, as if you retire 6 players per year, you will turn over your entire roster (with having 1 FP) every 6 seasons. So I think you may need to increase a players eligibility to 7 or 8 seasons at least. One other good thing about this is that it should bring back parity to the league, as all teams will be turning over players at a more rapid rate.
Just a thought, as I'm fairly new to the league and will go with whatever you decide.