IMO the wideouts are value picks. Reiff and Martin are off the board for me, and I'm not even sure that I'd take Brockers ahead of the WRs, and I really like wideouts.
I just think that you and Duck are being a little pie-in-the-sky regarding what the Cards could get for a trade-down. I don't think that you'll get 2 additional draft picks from ANYONE to move down 5 spots, especially if one of them is a second. The cost difference between 13 and 25 isn't great enough to justify the risk of not getting a guy you want.
I'd rather have a trained Floyd for our 2013 first-round quarterback then hope that we can bring someone better than Andre Roberts in next offseason. The best thing to do for a young QB is drop him into a situation where all the other pieces are settled. Even if (when) Kolb flames out this year, whoever we bring in will have Fitz, Housler, Ryan Williams, Wells for another year, and the defense. Add in a top WR prospect like Flyod or Blackmon, and it'd be a better situation than than what Mark Sanchez walked into, and he made it to consecutive AFC Championship games.
To respond more directly to your original post, I'd make my Top 13 board something like:
1. Luck
2. RG3
3. Kalil
4. Melvin Ingram, OLB, South Carolina
5. Claiborne, CB, LSU
6. David DeCastro, OL, Stanford
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7. Justin Blackmon, WR, Oklahoma State
8. Cordy Glenn, OT, Georgia
9. Malcolm Floyd, WR, Notre Dame
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10. Stephon Gilmore, CB, South Carolina
11. Mark Barron, DB, Alabama
12. Donta Hightower, OLB, Alabama
13. Mike Adams, OT, Ohio State
The tier dropoffs are where the dashes are. I'd be fine drafting 7-9 with our 13th pick. If none of them are on the board, I wouldn't trade down lower than 25 without getting a 2nd round pick and at least a 2013 second-rounder along with the pick. I don't think that price would be available for Trent Richardson or whomever, but maybe.
If we can't get one of those 13 guys with our first pick in the draft, we'll have screwed up the first round.