Who would like to have a future feature episode that focuses on either on just before you entered Starfleet/the kdf/arrived on virinat, or see how the Klingon anti-undine campaign started in a holoprogram.
A flashback episode would be amazing but would need a framing character like Q to actually experience this flashback.
My idea for a flashback would be that you are sent back to relive a time aboard your ship maybe that you are an acting ensign aboard your "starting" ship and there is orders for your ship to attack a Klingon fleet in federation space and on the day you are promoted to a full ensign your close friend is murdered and there could be an expansive story where you could take a shuttle or something to take revenge.
This is also usable for Klingon's as revenge is a required part of their culture
However, most of the RP'ers would probable not be so much of a fan, since they have already created back-stories for their chars, and such a mission would without a doubt be contradictory to what they've written.
In that case, how's this sound, we have Q send us to when some of the other races (Klingon, Andorian, Romulan, etc.) first did their warp flights, plus the post flight first contacts that happened as a result.
Adding to the warp concept: in my imagination, the Bolian warp ship is just a cockpit attached to the engine for budget reasons "they could afford the engine, just not a ship to put it in", and is found by a constitution class(not enterprise, too cliche) when it breaks down half way back home.
For the Gorn, race one(science) monitor's race three(tactical) making their first warp experiment, later explaining to race three how race one got to space first, but race two(engineering) broke the warp barrier first.
Maybe Q takes you back to Voyager where you meet Kathryne Janeway and the other characters or Q takes you back to Kathryne's ensign days? a character like Q could even take you to the time of the Enterprise Era and you could temporally play as Jonathan Archer and have a temporally control of the NX class (this would also budge people to buy the bundle or the ship as you would have a "test drive" of the NX)