I would return everybody else, but I guess you have to keep 6. Chris Davis for 15 bucks terrifies me, and Joba won't even start this year, barring an implosion from Phil Hughes or injury to another Yankee starter. Personally, I would choose to move on with Aceves/Avila for $3 and use the savings to bid on the free agents this year, rather than keep Davis or Peavy for 15/20 bucks.
I know the prices look hight for some of those guys....but our draft has such inflation it is crazy based on the amount of keepers. For example...last year Peralta 27$, Burrell 25$, Figgins30$, Meche 23$.....I know my league. All these guys are below what they would go for. Peavy would be 26, 27$ easy.
Since your league is AL-only, how do mid-season trades work? Say Adrian Gonzalez gets traded to an AL team. Do you guys auction him off then, or is it the 1st waiver claim who gets him? If your league is H2H and not Roto and you auction for these occasions, I wouldn't mind saving my money for something worth it like this instead of making Jhonny Peralta or Pat Burrell a $25+ player.