Legacy gets my vote, simply because its time Kim got that promotion. I heard whispers that he was supposed to captain the Voyager-B in PIC S3, so I've just got to see it to believe it. I think of the options, a young Picard series is one that I'd least want to see. All I can imagine is a space drama about a Picard/Jack/Beverly love triangle, weird cameos by characters we aren't supposed to meet yet and more arguments over continuity. Not fun The lost era has potential, but again its easy to slip up with prequels.(speaking as a huge Enterprise fan)
It was time 27 years ago, but I get the sentiment. I think that would be a nice "full circle" for the character.
I have to say, I'm coming around on the idea of a series focused on Rachel Garrett. It would give us a show to bridge the gap between TOS and TNG, but it would be focused on a character who's almost an entirely blank canvas. And, to satisfy those who want to see some of the usual suspects, they could still have a younger Picard and the Stargazer show up, but only periodically, instead of having a whole show focused around them.
I want something retro...with buttons and switches. Watching Disco now where everything is just so effortless and...pat.(Bah!)
Birth of the Federation show - fresh faces I guess goes without saying... but as many of the Enterprise cast who want to reprise. Including Connor.
Well that's kinda dour. Can't say it's an opinion I share. I'd hate to see the franchise flicker out so unceremoniously.
I would hope, sincerely, that Trek continuing on would be treated positively. But, today, I sit, feeling like no matter what Trek does it will be treated poorly. And that's more dour than any ending.