Schweini yes, although (i) we'd have to limit his wages which could be hard if anyone else is interested, and (ii) I'd expect someone slightly better to replace Nedved.
Busquets yes, why not take a chance? Never seen him play live though.
Stovini yes, solid experienced guy. Would be used as a fifth choice defender, à la Kovac, Stendardo, Knezevic.
Criscito back yes. Although that would have to be assessed by the coach and staff who know him better. Has he really improved since last year? Can he handle the pressure? Is he ok with spending 80% of the time on the bench?