This has been thrown around occasionaly on slashdot in the past and here's my fleshing out of the idea.
- first, start pre production soonish but hold off a few years, bring it out on the 25th anniversary of TNG.
- second, give them a decent ship that looks mean and doesnt have a barber shop onboard. preferably something akin to the sleek and fast-as-a-bastard Exelsior class
- third, show some of the dark side of the federation, TNG and DS9 occasionally allowed us a peek into dimly lit bars, spaceports and mercenary cargo ships, sure you don't need to go all the way to firefly extremes, we want it to be trek afterall
- fourth, give them a proper mission, or three over the course of the series' run, sure have monster-of-the-week episodes to get people interested but also expand on the DS9 theory of an overall plot (but at least decide in the first place what it is).
- finally, install a now older, wiser, and not at all anoying: Captain Wesley Crusher
Here's how i see it playing out in my geek brain, it just needs a few, er, important blanks filling in. the first half of the double-length pilot will see a retiring admiral picard meet up with Crusher at his ben kenobe style hut on some rocky planet somewhere. For $REASON (to do with his experiences gained whilst off with The Traveller perhaps?) starfleet have sent picard to get Crusher on board for $MISSION. They go off somewhere and get stuck up a mountain and after a reversal of fortune on TNG's "Final Mission" with picard helping him out crusher realises he now owes the old boy a favour. so he agrees to go along back to starfleet to check it out. Picard cheekily flies by the shiney new ship to bait Crusher along. and after having dinner with his mum, probably, Crusher takes on the job under certain conditions, especially that he wants a couple of his own guys on the crew (who specialise in Tactical and $SOMETHINGELSE), but not in a Maquis-on-Voyager-oh-dont-we-all-get-along-nicely-after-all way, more like Garak-and-Odo-on-Defiant way, not in uniform, not technically starfleet but under Crusher's command nontheless. For the hell of it you could throw in a bunch of rowdy often drunk klingons, instead of bloody vulcans. Crusher, being a kick ass pilot and engineering wizz will also not be entirely liked by the crew: the sexy assed Youngish ensign girl who he keeps supplanting so he can steer the ship himself (though they end up finally getting it on eventually, probably), his first officer, who's pissed that this guy just got handed a captaincy and he was overlooked despite years of butt licking and the Chief Engineer, because crusher's not only always interfering but also crashing into things.
Set them off on their $Mission, and let battle commence!