I think it would be a solid idea to find a trade partner with our first round pick. Have a team move back in to grab a QB or WR and we can pick up an early 2nd maybe 3rd/4th round pick.
There's a lot that goes into that. You have to be confident that the players projected to be available at the #27 pick don't represent good value, factoring in need, relative to the players you project at, say, #40.
According to the Jimmy Johnson chart, which surprisingly still holds fairly true in trades actually executed, the difference between 27 and 40 is not that great...you'd gain pick 82, middle of the 3rd. round. The CAVOA chart is less generous. It attempts to apply a statistical performance basis in measuring draft position value, with that method coming up with pick #174 as compensation, middle of the 6th. round. Whatever Harvard might say, GMs stick fairly close to the Johnson chart even since the rookie salary scale was implemented. CAVOA doesn't consider cost at all.
https://harvardsportsanalysis.wordpress.com/2011/11/30/how-to-value-nfl-draft-picks/
I'm sure Pro Personnel does some advance work regarding other teams needs, but that's only Kentucky windage. It only starts to get interesting as the picks in the 20's come off the board. You get some idea of where teams will be picking through #39 and whether there are a few attractive names still on the board to choose from, one of which is likely to be available at #40.
There is a tight time frame to make the assessments and then find a willing trading partner.
Consider the Nelson trade. The #30 was traded away for the #36 plus a 4th. rounder. Was Nelson the only guy Thompson was targeting? Not likely; Thompson is a risk averse guy. He likely had more than one name in mind, maybe several, that he thought were good values at that spot. Is it possible he had 4 names in mind, they all got taken in front of him, and Nelson was in reality a reach? It's possible; after the fact, of course, nothing but good things will be said. Who in their right mind would say, "that's not what we wanted to happen".
Further, in recent years where there was clear strength at one or two position groups, there has been a run on those groups whereby the value proposition was not so exceptional by the time the #40 rolled around. Once top-of-the-board teams get their big need guy in the first round, usually at the high demand positions (QB, OT, WR, perimeter CB, edge rusher), they could swarm on any high value DTs left in the 32 - 39 range.
Add it all up, and there are many factors that inhibit a value-added trade down. It's not something you just do at that level of the draft board.