It's spring 2005. The show just got cancelled. You work on the show, and you've got Berman and Braga's ears, you're helping work on the series finale. It's going to be a 1-hour, and it's gonna be a TNG crossover to bring the 1987-2005 full circle. Valentine for the fans! That's the starting point. How would you make this work as a series finale where you're not spending the next few years denying to have been involved? 
Changes I'd have made, trying to keep the episode as is, but make it work.
#1 Make everyone look 6 years older, possibly new hairstyles, plus Reed, Sato, and Travis are all promoted up at least one rank.
#2 If B&B want Trip & T'Pol broken up, have it be more recent so it can tie into the episode itself.
#3 Killing off Trip isn't a big deal; they knew it was over and there wouldn't be a movie.
#4 If you're killing off Trip (my favorite character), it needs to flow better into the plot. Blowing up space pirates (and himself) is just... random.
#5 There's just "too much" going on for a 45-minute finale. Let's check: six years later framing, TNG holodeck framing, NX-01's final mission, Shran's daughter rescue mission, space pirates, main character death, Riker and Troi's "Pegasus" plot. Two framing devices, 5 stories, all in one episode.
#6 Maybe UPN could have pushed it to 23 episodes so the finale could be a two-hour? Yes? No?
#7 The uniform and set updates for the "6 years later" stuff was stupid. Just leave the uniforms as they are, focus on making the ship more weathered looking, and if you're going to add shit to the set, make it look functional and blending in, not those random add ons from the old NX-01 from "E2."
#8 Slim it down. 6 years later? I'm good. TNG framing with Riker and Troi? I'm good. Frakes and Sirtis pretending to be Riker and Troi from 1994 in a 2005 episode? A lot of casual fans loved it, so it could have worked. This needed to be very much an NX-01 story "watched" by Riker and Troi. The A-plot should be the NX-01 doing X on the way back to Earth, whatever that be. The B-plot is fine as Riker and Troi, so long as it made sense. The whole episode should have built up to the death of Trip.
#9 Maybe pick a different TNG S7 episode to tie into?
#10 Maybe tie the episode into Nemesis?
Anyway, point is, I liked the TNG crossover concept for the series finale, history looking back on the NX-01's final mission.
Conceptually, good ideas. I feel like the rush job is what killed the final product.

Changes I'd have made, trying to keep the episode as is, but make it work.
#1 Make everyone look 6 years older, possibly new hairstyles, plus Reed, Sato, and Travis are all promoted up at least one rank.
#2 If B&B want Trip & T'Pol broken up, have it be more recent so it can tie into the episode itself.
#3 Killing off Trip isn't a big deal; they knew it was over and there wouldn't be a movie.
#4 If you're killing off Trip (my favorite character), it needs to flow better into the plot. Blowing up space pirates (and himself) is just... random.
#5 There's just "too much" going on for a 45-minute finale. Let's check: six years later framing, TNG holodeck framing, NX-01's final mission, Shran's daughter rescue mission, space pirates, main character death, Riker and Troi's "Pegasus" plot. Two framing devices, 5 stories, all in one episode.
#6 Maybe UPN could have pushed it to 23 episodes so the finale could be a two-hour? Yes? No?
#7 The uniform and set updates for the "6 years later" stuff was stupid. Just leave the uniforms as they are, focus on making the ship more weathered looking, and if you're going to add shit to the set, make it look functional and blending in, not those random add ons from the old NX-01 from "E2."
#8 Slim it down. 6 years later? I'm good. TNG framing with Riker and Troi? I'm good. Frakes and Sirtis pretending to be Riker and Troi from 1994 in a 2005 episode? A lot of casual fans loved it, so it could have worked. This needed to be very much an NX-01 story "watched" by Riker and Troi. The A-plot should be the NX-01 doing X on the way back to Earth, whatever that be. The B-plot is fine as Riker and Troi, so long as it made sense. The whole episode should have built up to the death of Trip.
#9 Maybe pick a different TNG S7 episode to tie into?
#10 Maybe tie the episode into Nemesis?
Anyway, point is, I liked the TNG crossover concept for the series finale, history looking back on the NX-01's final mission.
Conceptually, good ideas. I feel like the rush job is what killed the final product.