I think it was the opposite. He held on to his prospects (mainly because they didn't have much value to other teams) and paid top dollar via free agency. Off the top of my head, the only players he drafted that he traded for immediate help were Dave Bush, Zach Jackson, and Adam Peterson. He practically held on to everyone else until they either contributed (Hill, Lind, Marcum, Romero, Janssen, Litsch, to some extent Snider, etc) or washed away completely (Adams, Purcey, etc).
I have said before, Ricciardi's biggest weakness was drafting. Other than that, he knew team building. He valued OBP, pitching, and defense. He didn't trade his farm system for immediate help (Bush aside). He overpaid to get free agents instead of overpaying in prospects/assets. Give that man an actual farm system (in other words, give him absolutely no control over amateur scouting) and he'd be a great GM.