I wanted to see Sisko and the crew have to deal with the Borg. Because the Borg and their actions were a big part of Sisko's life. And along that vein, I wanted to see one episode where Sisko and Paicard had to work together, because of Sisko's resentment of Picard for killing his wife when he was Locutus. We got a brief view of that tension in the pilot when Picard gave Sisko his mission...I always assumed it would be followed up and and maybe resolved at some time in the future. But it never was. Andorians. I wanted to see Andorians. I think it's a shame we never saw Andorians in any of the TNG era series. (Hopefully they will show up inn Picard.) Bajor finally, formally joining the Federation. It seemed they were always building up to it...then we never saw it.