At this point, I think there's sufficient uncertainty in the top tier to not rank them against each other. Citadel beat Furman, but has more losses. Wofford has looked impressive, but we don't know how they match up/compare to the other two as they've performed better/worse/about the same with comparable competition (with the exception of Samford). Furman has the most recent loss and question marks on offense, even though I think they'll be resolved soon enough.
Tier two is teams that have either beaten or played tier one competitively, while also being competitive with each other. They have consistency problems, which at this level is the difference between being an average and good team. Tier three are the teams that consistently lose.
Wofford @ Mercer
Chattanooga @ Samford
ETSU @ Western
VMI @ Furman