Ledley would be a great addition. Terry is a no brainer for me, the guy is a leader & winner. We'd be fools not to take him.
If he became available, would take Calum Chambers or Rob Holding with a view to a permanent. They won't be getting much game time at Arsenal with their options at centre half.
I would love to see Andreas Christensen from Chelsea, but I reckon there will be more after him. Nathan, Wallace, Matt Mizaga, Izzy Brown, Kasey Palmer are others I would take from Chelsea. Get Terry to have a word!