This is an OK standalone episode, I think. I don't feel as negatively towards it as some people. I would agree that it's possibly the worst episode of the 3d season, but the 3d season is so fantastic that that doesn't say much at all.
The twist on the bodysnatcher story works well, I think. I like the idea of the Vindrizi, and the effort to preserve the past for the future is something I can really get behind
This storyline also includes the common theme of self sacrifice in Duncan sacrificing himself (or his Vindrizi self, anyway) in order to convince Dr. Franklin that his old self meant/agreed with the things he said about the Vindrizi.
It's really not a bad story, overall. And it gets us some interaction between Franklin and Marcus, which is nice. I do like the Marcus character, and his English literature spouting.
As for the other storylines in this episode, I dig the Lt. Corwin stuff. I always liked the Corwin character. His awkwardness is entertaining. He also looks JUST like an old roommate of mine, who was just a little younger than Corwin is here when we watched Babylon 5 together. That made watching Corwin bits even more entertaining. I feel about as disappointed as Sheridan looks when he finds out Corwin can't be included in their secret meetings and such, but I'm sure it's more interesting this way.
The Ivanova and Corwin interactions are funny. I also like how the flower "incident" leads Ivanova to throw those roses at Marcus at the end, who is very surprised and happy. I'm not usually too good with confusion/misunderstanding humor, but this was funny to me.
Tiny details and what they may or may not mean:
More about links: I talked about this a little bit in the "Voices of Authority" thread (it's a very public way of communicating), but here's some other details we learn about communicating via link in the B5 universe: Marcus is unable to use Franklin's link. Those things apparently have bio sensors of some kind. That seems like a good safety feature. It raises some questions about that time the Green Drazi used Ivanova's link in The Geometry of Shadows. They must have either forced her to use it, or used it while holding it against her skin (seems more likely). It's also good to know that unauthorized use of a link sends an alert.
What we also see here is that apparently a connection isn't made just by pushing the buttons. Dr. Franklin gets cut off while he is trying to contact security and no message goes out. That makes sense, considering those buttons are so prominent on the outside of a thing you wear on your hand. I'd be pushing them on accident all the time. It does mean their voice recognition has to be pretty good
Synthetic roses. Do you think the fake flowers of the future fade for extra realism?