It is extremely difficult for me to believe that someone watching Babylon 5 as it aired on a typical sized CRT television thought the effects looked "cheap". Hokey? Okay, maybe, that's subjective enough to be non-debatable. But "cheap" in the context of a television show? The shots were so much more dense and dynamic than what Star Trek was doing at the time, which is the obvious comparison.
It's the season one acting that I find the biggest barrier to entry. It settles in by the end mostly, and the acting markedly improves from Season 2 onward though it always retains some of that campy scifi feel.
The costuming and sets and CGI are impressive, but the lighting is unnecessarily murky and the dark industrial tunnels aesthetic makes me think of Red Dwarf, which I can’t imagine was a very lavish production.
The earlier Red Dwarf episodes were filmed in the BBC cafeteria and other similar locations. The difference is that Red Dwarf was supposed to look grimy. They were on a mining ship with few luxuries. Red Dwarf was more in the territory of Dark Star, and played into that. (Early Red Dwarf tended to use physical models and costumes for a lot of effects. CGI has never been especially great on RD.)
I did watch Babylon 5 when it first came out in the UK. Deep Space 9 definitely had better looking effects, but I preferred B5 to DS9 on the basis of other factors.
I think B5 has a variety of environments, and some of them are quite nice, and I like the moody bustling alien cantina type spaces. But they also have too many dark industrial passages, which doesn’t always fit the scenes and come off rather cheap.
It's the season one acting that I find the biggest barrier to entry. It settles in by the end mostly, and the acting markedly improves from Season 2 onward though it always retains some of that campy scifi feel.