Generally, I think it's the other way around, where most fans tend to overrate draft pick potential in hypothetical trade scenarios. I think we saw this a lot here in N.England recently with guys such as Cassel, Meriweather (first round 2x pro bowler who was an outright cut), and Mallett.
If the Seahawks are planting the seed of wanting a 1st + something else, they'll likely get it in my opinion, and rightfully so. Kam Chancellor is one of those proven value safeties that while probably overvalued, will instantly demand the type of value normally reserved for "elite" talent.
In my opinion, there's only a couple/few/several players on each team who are worth a 1st round draft pick, particularly now since the rookie salary cap has been implemented and we're no longer seeing 60+ million dollar deals for unproven players like JaMarcus Russell. In the day and age of the salary cap, 1st round picks are more valuable than ever.