Whenever this subject comes up, it bugs me that people try to use the other leagues as an example for how to implement a cap and floor for MLB. The financials for each league are completely different, especially the NFL, so saying that there should be a floor that is around 90% of the cap like the NFL has is just wrong. The least valuable NFL team is worth 6 billion while MLB has two teams with a valuation that high.
I have no idea what the numbers should be but just looking at the payrolls from last season, lets say a cap of 250 million and a floor of 150 million. That reins in the big spenders while forcing smaller market teams spend more. While were at it, they need to address this crap with deferred money. Player contracts should be for the seasons they are signed to play for your team, not something you'll be paying them a decade or more after they've retired.