Of the "name" guys out there Monroe certainly seems like one of the few we have a realistic chance at getting. The dollar amount would probably produce some sticker shock but Danny has a habit of inking deals that seem like overpays when they're signed and bargains before they end (Rondo's extension, Bradley's deal, etc).
On the court, defense would be the big concern, and I don't know how he'd feel about playing C again, but he'd give us a real playmaker down low and contribute to our rebounding, scoring and ball movement. I'd have mixed feelings about the signing but I'd certainly give him a chance.