Both of those stats point to the midfield. The game is all about pressure. If you allow the opposition mids to kick without any pressure, they can put the ball exactly where they want (hands of their forwards).
Lever is just a more aerial Hibberd. Both are very good defenders, but both won't stop the likes of Brown, Daniher, etc. if playing man on man.
Omac will again put on muscle in the off season. He will be a Talia or May and will be able to handle the gorillas, but that will be in time. There is no one else coming through, and if Garland were fit, I think I'd prefer Omac.