Logan is a decent scatback type RB. A quicker more explosive Johnny Augustine. Also he's a solid if unspectacular returner as well which helps his value. I'm thinking he'll be the starting returner and change of pace back for Oliveira with limited O touches unless Brady goes down.
Vaughters was once an elite pass rusher, but that was a long time ago. After solid success with Stamps in 17-18 he went down south where played as a rotational OLB (edge rusher) and STer for quite a few years. Came back to CFL in 2023 I think and has never had that quickness off the line like before, but he's turning 32 in June so that makes sense. Quality veteran DE, but ideally he's a DE3, IMO.
Jones i don't know that much about tbh. I vaguely remember him in TO over past 3 years, he's been ok but not a standout as far as I know. Looks like he's had injury trouble as well.
