Birthright
This is a very unusual two-parter given that the A-plot (Worf's) stretches over two episodes whilst the B-plot (Data's) is sketchy at best and doesn't go beyond part 1.
It seems to me that they should have made Birthright a Worf only story, including the clever use of DS9 where he receives the intel on the Romulan camp. On the other hand, Data's "accident" could have been caused by some other plasma-discharge and I don't feel that Bashir made a profound contribution to the episode. Half the observations he made could easily have gone to a regular Enterprise engineer such as Barclay or Lefler, or just Geordi to help develop the relationship between them.
I'm not sure if Data's story could have filled a full episode easily on its own, but I think it could have been much improved and run as an A-plot against some other B-plot. For example, it seemed very odd to me that Deanna Troi did not make any attempt to counsel Data on his experience and advise him how to proceed – it would seem to fall into her "area of expertise" to some degree. Just goes to show that she's only a busy-body when it suits her.
Naturally, they couldn't have made two unrelated TNG episodes back-to-back set on DS9, but omitting Bashir completely and finding another way of triggering Data's dreams, then expanding Worf's time at the Romulan camp would surely have been better. The BluRay has a number of lengthy deleted scenes from part 2 which would have worked. We could have learned more about Mogh and his death, seen more relationships between the Klingons and Romulans than just dinner, and gotten a much better picture of their coexistence and daily lives.
The episodes are not too highly rated, part 1: 7.6, part 2: 7.3, which seems to reflect the fact that there were some good concepts which were poorly employed. Birthright ultimately lets itself down by doing too much in part 1 and not enough in part 2. The overall result is a lack of focus, under-developed ideas and a weak conclusion for both Data and Worf.
Welcome any further thoughts.