I really miss the Versatile option here, as I think half of the mentioned characters would fall in this group (Justin seems to top unless he is with Brian, there are mentions of Ben on the receiving end of gang-bangs, Ted is seen in both roles, and we don't know enough about Blake to be really sure)
To me it looks like we have two characters who prefer to bottom and two who prefer to top (Michael/Emmett and Brian/Drew) - that in turn forces two other characters (Ben and Justin) from V to T/B respectively
So rather then having four T/B pairings I see one of each: T/B (Drew/Emmett) T/V (Brian/Justin) V/B (Ben/Michael) V/V (Ted/Blake)