Kinda what I was gonna add.
I'll 1st admit, and not criticize others
(I know sometimes how we can type something as simply a here's how I do it-type statement and it can be misinterpreted into a criticism), that I'm just looking for a way to stop the offense and push them back playing a field position game.
FIRST thing I look for in OLB is SPD of high-80s, and an appropriate ACC measure. Not a lot of those in ea. class so my '1b' thing is to look at SS (and sometimes even FS) recruits for this. Then I look at tackle and block shed. Perhaps finally, I look at man & zone coverage ratings, but if they're speedy with great coverage but tackle or BSH poorly, I'll keep looking.
This plan fits in really well w/ my 'look at SSs' idea since they generally have higher coverage ratings. Another bonus is I'm finding more times than not they've also got better Play Rec values.
Currently both OLB positions on my team are class appropriate (Sr, Jr then So, or RS-Fr) with one starter speed at 95 and the other at 98 (tied with WR for 'fastest' on team), and 2nd/3rd guys trailing appropriately with progression improving them closer to those same numbers ea. year.
They just fly to the ball and I'm getting really good at 'B switch' and making tons of "User tackle for loss" plays.
I basically utilize the same plan for MLBs but I'll look for maybe a higher tackle ## and will allow speed to be in the low-80s. Many times the transition will show a higher OVR of maybe +1 at DE but I often keep these guys on the 2nd line in the middle-backer spot (did the opposite of this this year, tho, as I got caught w/ my pants down not being attentive enough to the upcoming years at replacing a pair of top-notch DEs and had to shore up the position, unsatified with what I had there on the depth chart).
Bottom line for me is an established recruiting plan that lets me transition guys upward into starters over time rather than having to rely on a So. or RS-Fr. I basically never have 3-yr starters at OLB and its not the norm, but I've had it, at MLB.
On a side note, my SS to LB idea also allows me -- don't know how others set up their rosters and depth charts -- to keep only 2 guys at FS and SS sticking a 3rd OLB into the 3rd spot in those secondary spots, since most times it's a converted guy anyway. I don't like using CBs in these 3rd spots.
Anyway, lots of folks probably do the same thing, these are just my ramblings on how I created a Linebacker lineage...