I know you have already edited a few things already, but if I were to take a guess at a potential issue, it would be the SPARTAN contingent. It's not an issue of their power or ability as much as just believability. It would be almost unheard of to have that many Spartan-IIs in one place at most points in time, let alone late in the war. I would find Spartan-IIIs more believable, personally. There were only about 33ish Spartan-IIs that made it through the program. I might just be being particular, but...we do have a few Halo fans here. As for a believable number of Spartans, I'd have to leave that up to the GMs.