The 30th pick has a lot more value than the 33rd pick because of the 5th year option.
If I'm sitting at the end of round one I would always be looking to trade down. Last season Seattle traded the 30th pick to the Giants for the 37th, 132nd and 142nd picks. Seattle traded the 37th pick to Carolina for the 47th and 77th picks.
So they sat with 47, 77, 132 and 142 for the 30th. That's a 2nd, 3rd, 4th and 5th rounder for the 30th. You can find good interior OL, ILB, RBs, TEs, WRs. All needs on the current roster.
Big drafts lead to big improvements more times than not. More picks mean more chances to find gems.