Yes, I know that the Neutral team is also Red, I just can't think of a better color. (Gray is a radar color for cargo regardless of IFF).
-Anyway, any team you're not on - except Unknown will appear Red to you, and ALL of your teammates are green. Except if you are Unknown - I tried making the Friendly team Unknown once - I used Wordpad - all my teammates (unknown) have PINK brackets around them, even though they are green in the radar.
Let's have other teams appear just red. Unless the mission designer said so.
For the alliances, I did think that over and I thought simply additional wings may be better, especially if the maximum players was increased. Team Green will be Alpha and Beta, and Team Red will be Zeta and Eta, etc. So it would be an 8 vs. 8 team. Of course if you do that you would be limited to two teams if it was 16 players max.
The "H" key, does get ALL teams that are not on yours, except Unknown. AFAIK, NTF ships are neutral, including in Multi. Not sure in TVT though.