A few points...
1. The best way to extort a trade isn't by hinting that you "love" a player (Richardson) that a potential trading partner covets (because if he were there at #13, you'd take him yourself). The more traditional way would be to drop the hint that at least one other tam was trying to trade up to get RIchardson or someone else.
2. If you're really interested in trading down, you'll be prone to failure if you lock onto one single player you've got to have (Chances are better than even that he'll be gone).
3. What's missing in the process is a Cardinal Top 17 - are there 17 players we'd be happy to use our first pick on?
Off the top of my head - Luck, RG3, Richardson, Blackmon, Floyd, DeCastro, Martin, Coples, Keuchley, Clairborne get me to 11.
You could make the case for Upshaw, Ingram and Glenn to get to 14 (though Ingram and Upshaw make me nervous).
(I'm not sold on Reiff and K Wright is dropping out of my top 20).
Who would be the other 3? A strong case could be made for the top 3 NTs (Brockers, Poe & Cox). That gets me to 17, Reyes (who reminds me of Dockett) would put us one over at 18.
Bottom line - I think we do that deal if we can get it (unless our FO is in love with someone like Kalil or Richardson & he falls into our lap at #13).