I'd forgotten that TGoS does feature the prophecy about Londo that we later see in dream/vision flashes in The Coming of Shadows (more on that in a sec), but even that isn't enough to make the episode significant.
I did say I'd be back with reviews of episodes 9 through 12, so here we go.
The Coming of Shadows
I loved this episode. It does a masterful job of throwing the story arc for the season into high gear, and also gives us a full season's worth of character growth for a number of characters, particularly Londo. As I was watching the episode, I kept being reminded of these words from Albus Dumbledore - "Soon each of us will face a choice between what is right and what is easy" - which sum up Londo's actions here pretty succinctly. He makes the easy choice here rather than the right one and it's going to come back to haunt him.
I got a very strong sense of deja vu as I was watching GROPOS, to the point that I felt I could've been watching my all-time favorite TV series, BSG. I believe I mentioned during one of my earlier reviews that one of the episodes reminded me of the BSG episode Unfinished Business, but GROPOS didn't remind me of BSG, it felt like BSG. The relationship between Richard and Stephen Franklin felt like the relationship between Lee Adama and his father, and the GROPO private Dodger felt like the B5 version of Kara Thrace, and would've been an excellent recurring character.
All Alone in the Night
AAitN is an interesting episode because it is both easy and hard to determine the episode's significance, which hadn't been the case. On the one hand, you've got Delenn's storyline, which will take on incredible importance, but you've then got the Sheridan story that is perhaps a bit too ambiguous. The things we find out in the episode concerning the thinking behind Sheridan's assignment to the station really help inform his character and also dovetail very nicely with his actions in Spider in the Web and A Race through Dark Places, which only helps increase the significance of those two episodes.
Acts of Sacrifice
You could almost call AoS a sequel to both The Coming of Shadows and A Racd Through Dark Places, because AoS really starts to show us for the first time the tangible consequences of the events of TCoS and gives Sheridan an opportunity to rely on the resources and resourcefulness of Franklin that he becomes aware of in ARtDP. The 'b' plot involving Ivanova adds some lighthearted fun to the episode and serves as a nice counterpoint to the episode's more serious 'a' plot, and also let's Claudia Christian show off her comedic chops.