Williams = Huge risk + Small reward.

Williams is not well known. Williams has too many phisical advantages to even count. Williams throws 100+ punches. Williams is lefty. Even if Floyd overcomes all these advatages and wins easilly, most boxing fans would just shrug and say "so what, who the fwok is Williams anyway"

The only way Floyd fights Williams is if he cleans out the division and there is no one left for PBF to fight.

As for the original question. Anyway you cut it. Floyd has very few options other than a rematch with DLH for another big paycheck which would make me puke. He could move up but there is really no one worth fighting at 154 and that only leaves 160. With Kelly Pavlick there now that would be comiting suicide.

He could move down and temp one of the lightweights to move up but what would be the point.

Alas he is in Roy Jones Jr. in the 90's shoes. Too small to move up and too skilled to move down. He can either retire or do what Roy did and simply stay there and dominate and hopefully realize when it is enough and get out of there before he gets KTFO.