[@Jabber] I thought I had something for that at first, but then I realised that the system I would've suggested is extremely general in terms of tiering. And as a matter of fact, so are most power tier lists I've seen - for instance, a general "street tier" might exist which covers everything from sub-muggle to block-busting, or something along those lines. Which is great in terms of description, aside from the fact that that's a relatively huge range of power when considering such low values, and they only really get more stretched out as the scale increases. That said, if you could reliably apply feats to each rank of Marine based on what an average Marine of that tier can do (and disregarding those who are ranked below their actual power, of course), what I said might still be applicable as a system, but... well, good luck with that.