It's Troi who takes a crack at Worf, while inhabited by an alien psi force that can increase her strength without any after effects for her.
Why didn't Picard say "Leave a warning beacon" at the episode's start? Surely other, less obvious clues, might come back to haunt them?
For some reasons, a crewmember was involved before their memories were wiped out. Crusher did this, Troi did that, Data did the other thing.
Why not order Data to erase his memory instead of keeping his mouth shut? It would be accessible by the Borg, Lore, or anyone else who could tap into Data's memory cells. It would make the mystery even darker and would have been a terrific spin, nor having everyone question Data - which in of itself is a fair idea, but it doesn't come across as well as it could.
While the first three acts are somewhat tedious and it's clear Data is hiding something. But the final act does convincingly make the whole affair believable despite its flaws.
Not bad, but by no means perfect.