Two other middle linebacker options besides Zaven Collins at 28: Jayson Oweh and Joseph Ossai
Urlacher was a natural born ball player. He was as pro ready as any LBer you'll see. While Oweh compares favorably to him athletically, he's still learning the game. If you're drafting him with the idea that he can be an every down LBer it's possible but it could take some time. But if you're drafting him to be a pass rusher I think he could have a more immediate impact there.
I hear what you are saying but look at Connor Barwin. I suggested way back when that he should be an OLB but the Texans started him a DE instead.
Even though he still had a respectable rookie season with 4.5 sacks and 8 qb hits in a rotation role he still fared much better in his very first year at OLb in 2011.
For a guy with all the requisite elite traits for a linebacker I really don't think that the transition will take quite as long as you think.
"Barwin returned from injury and moved from defensive end to outside linebacker in 2011, starting all 16 of the Texans' games as the Texans advanced to the second round of the AFC Playoffs. On November 27, 2011 Barwin established a career-best 10
tackles and a new franchise record for
sacks in a game with four in the Texans' 20–13 victory over the
Jacksonville Jaguars at
EverBank Field;
Mario Williams had previously held the Texans' single-game sack mark with 3.5.
[13] He was named AFC Defensive Player of the Month for November.
[1] Barwin finished the regular season with 49 tackles, 11.5 sacks, seven passes defensed, and a forced fumble.
[14]"
https://en.m.wikipedia.org/wiki/Connor_Barwin