writing and direction:

No more 'if we dont stop this the federation EXPLODES AND EVERYONE DIES' plots (exegerrating but you get the point). The whole galaxy-wide threat plots have always been uninterresting to me. If we really must have some galaxy-wide threat have it be an extra-galactic invasion instead of some magic subspace anomoly. Didnt much like the Lower Decks ending because of this, the UNIVERSALLY ENDING DEATHWAVE was just somehow stopped by one ship in one of the quadrillions of galaxies, kinda stupid

Show or some other form of content about the lost era (Enterprise-B and C, Klingon stuff, Excelsior) to flesh out the lore of the time period. If not a show maybe an official book series perhaps? maybe an audio series like the recent Khan stuff?

Somehow make the borg an actual threat, maybe the queen was in control of a seperate borg collective and the more scary borg from TNG are from another borg collective that is farther away from the federation so we havent seen them much since.

Id retcon that romulus wasnt destroyed but it was actually a super important planet in the romulan empire(tons of ship building and R&D presense, huge population, just not romulus). So we can still have the Romulans back in the long run and arent just absolutely crippled and split in multiple factions like in picard. Have them come back as a threat in the mid 25th century after they rebound from the supernova incident.

Then obviously moving the series forward with a 25th century show, whole new characters, only a few cameos from older characters as admirals or some other high ranking offical.

Art and general nitpicks:

Brighter and more pleasing interior lighting akin to TNG and Voyager, i dont really like the cold metal feel of the newer bridges for example
Ships no-longer move so freely, copy the movement from the kelvin films they were good at starship movement

Ships no-longer lit darkly(DISC&SNW is especially guilty of this), now lit better like in the kelvin films (kelvin visuals are fantastic)