1. Must be set in the future relative to us.
Don't see any way around this. Can we go further Temis the Vorta and say No time travel?
2. Must focus on Starfleet.
Yes and no, it must be a Starfleet-like organization.
3. Must include (not focus on) the Federation,* as an ideal if not as an existing entity.
Not necessarily. While admittedly Enterprise screwed up the time period, a show set prior to the advent of the Federation could be made to work. Just need new creative angle.
4. The political philosophy of Starfleet and the Federation must be secular liberal humanism, with the Federation serving as a utopian exemplar of that philosophy.
Keep the Humanism, junk the "secular liberalism." Sure a
few of our characters will embrace that philosophy, but most of the new characters must be a diverse group in terms of their beliefs. economics
, religion, politics, culture, diet, nationalism, capitalism
, socialism. The principal characters are very different from each other. And the members planets of any Federation council shown will be the same, diverse.
There's a lot of different ways of doing things,
for the purposes of story-telling the show will embrace this.
5. This is what I mean by "not focusing on the Federation." The Federation is an off-screen ideal; the action takes place everywhere else.
Some of the best episodes have taken place on the "interior" of the Federation, DS9 rarely engaged in exploration and many (not I) consider it the top trek. Just because an episode features the Federation doesn't meant it has to revolve around the federation council, we can explore the peoples of the Federation, they're probably an interesting bunch'.
Without the Federation to serve as justification for Starfleet's activities, those activities had no moral weight.
TOS's moral weight came from Kirk, not the Federation. TNG's moral weight came from Picard, not the Federation. Contrast Picard (and TNG) with Sisko, who "worked" for the same Federation, but possessed far less in the way of morals - and so did DS9 in general.
ENT would have done okay if the point of the series had been setting up the founding of the Federation, which would have happened during the series run.
The episode of Enterprise that depicted the actual formation of the Federation is considered the worst single episode of all of Star Trek (TATV). The building of the "interstellar coalition," debatable, is part of what killed the show.
