if you read onyx and the new book glasslands (havent read glasslands yet) the spartan 3s kurt trained are trapped on onyx and are in the new book glasslands ,this glasslands book tells about kurt who went "M.I.A." and his spartan threes tom and lucy and a few others from onyx in some sort of mission that takes place right after halo 3, halo 4 is a year after halo 3 ,so halo 4 is in 2554, and i think it would be cool if thhey were to join chief with for sure U.N.S.C troops (you can see a pelican in the teaser art for halo 4) ,most likely elites, maybe other covenant species. BUT i think as far as characters go a spartan team for the chief would be great. in odst and reach it was great to have a team with reliable characters instead of really just chief and cortana. i think characters inrich the storyline