Reeder (4.64) is faster than Jones (4.73). Reeder is built like a LB at 6'2" 245lbs but runs like a SS. Reeder's production last year was much better than most people realize. He only started 7 games and only took 41% of the defensive snaps. Yet he garnered 2 PD (he's not the liability some claim), 81 tackles with 53 being solo, 5 TFL, 3 sacks, 4 QB hit, and 1 QBKD. His PD stats are good for an ILB. If you compare Reeder's stats to any good MIKE they will compare favorably. That's why I think it would be beyond foolish to replace a guy on the rise. Finding a good MIKE isn't as easy as most assume. More importantly, he's been durable.
If Morris adopts cover 3 as his base scheme as I think he will he will play both Reeder and Jones together as his two ILBs. With Scott or Burgess, Morris has exceptional speed in a safety to cover a Y receiver yet with enough size to provide good run support as well. If a vet LB is in jeopardy it's Young. I think Reeder and Jones would make a good pair inside.
Again it's pretty obvious from this draft that the Rams want to shore up their run defense and in doing so give Morris more options on using his players. It's going to be fun to see how this defense is played by Morris.