As far as my ideas go, as much as I'd like to see an Enterprise-F show that actually moves the story into the future, I think the "Lost Era" is the biggest goldmine for Star Trek that they've, up to now, completely whiffed on.
An Enterprise-B show would be perfect right now. George Takei is still alive and so is William Shatner. Have something happen to John Harriman (original Enterprise-B captain) which prompts them to give control of the ship to retired Captain Sulu. Maybe even on a provisional basis, IDK (depending on Enterprise-B's fate in the canon as it stands now). Sulu was a hell of an Excelsior captain in the past, after all. Then we get a sort of sequel to the original show that tries to capture the spirit of the original show. Visually themed after the movies (ST6 and 7). Excelsior is such a gorgeous ship and it's a crime that it never got a show of its own. Imagine William Shatner showing up to cameo somewhere. I know he can't because of the events of Generations, but I'm sure there's a way. Perhaps an alien reads Sulu's mind and transforms to look the way Kirk would look now in order to fool Sulu and crew. In other words "Kirk" could be a major antagonist as Sulu tries to stop him from desecrating the memory of the real Kirk. I'm going off on a tangent though. The point of this show would be to carry on the spirit of TOS/the movies while giving us one last chance to see these actors again (the ones that are still alive).
Then Ambassador could be like the TNG to the previous show's TOS. The next generation of Enterprise, on a mission to spread goodwill and form new alliances. While the Enterprise-B show would be a callback to the Trek of olde, the Enterprise-C show could explore new concepts and have more of a TNG vibe (less action, more cerebral themes). Since this era is largely a complete mystery in the lore, they'd have tons of leeway in terms of what happens. All we know is that it'll end with a massive climactic battle against the Romulans at that Klingon outpost that results in the Klingons joining the Federation, cementing the Ambassador status of the ship and crew.
Or we could just do a Clone Wars style cartoon about nothing
i dont want to see anything from the TOS era or those characters - they all fucking suck
give me new shit.