In the new rules, the fleet composition rules first call for all players to first agree on Core Force Type (Air, Land, Sea), the Max Points, and Theater of Engagement (primarily Land or Water terrain).
Minimum force requirements still apply. At least one Large or Massive, one Medium, and one Small squadron from the Core Force Type. Attachments don't count towards this minimum.
Percentages have been added. You must have at least 60% of your points allocated towards the Core Force Type. In addition, there are Max percentages for each size category. No more than 60% towards Large and Massive, no more than 60% towards Mediums, and no more than 40% towards Smalls.
Allies are allowed with player agreement, but cannot be more than 40% of the total fleet points. Page 190 of the rule book lists ally options.
You still get 10 free wings of Support Aircraft (Tiny Flyers).