I had Andrews pegged to go there for Norv Turner's power game, but now you have a guy who likes the slide screen more than the blast I formation as an O position coach in Trestman. He can still call the run, he did so as assitsant to Marty at Cleveland.
Andrews is monster runblocker, he can get your man four yards before contact. With a great TE to put on his outside shoulder and Konrad to chip block he will do fine. He takes a guy's first step away after about four good pancake blocks.
Zod is correct, this team has a vet D nulceus and is ready to make a run for it RIGHT NOW. A rook curve can come from Rivers round 2 or 3 with his feet to make plays when his experience can't.
Roethlisberger and 2 others are round one material anyways, they may be gone by ten.
Andrews will give Ricky 4 yards per carry to his side per play, and set up the great counter once teams force you to slant to that side. Plus you'll need 9 in the Box with his run blocking, he can turn a nose up defender in to pursuit down the line and allow a pull man to kick out the edge.
That makes DB gunshy for run support as well and helps Ricky run more.
I expect Marty or Oakland to get Gallery, the Giants may want Andrews,if Tuna was still there they would get him, a new Jumbo Elliot. Andrews is a cornerstone. Perhaps they'll get a for sure QB prospect to groom after Collins and his backup (Graham?).
If you let your DE go then it is likely that you get Andrews PLUS another impact first rounder, but quality DE is a must have and he can really be a playmaker.
Marino will probably go D and run game FIRST- like he did in his college days with Pitt. He knows how much that protects a young QB. Just my take on it... I really think Rivers will be available round 2, or the DE franchise tag can work it. All depends on how cap savvy the newcomer can be.