Well, opinions stay opinions.
Don't get me wrong, I am a very open person, but reading BSG next to the other (really great) shows made me shiver.
You are right, some actors were very bad in B5 - but some were genius (Katsulas, e.g.).
Well this mostly also has to do with budget.
Also, the storyarcs of B5 are still one of the best writings (in terms of WRITING) for any space opera, creating a very epic feeling until the show unfolds into season 5. Many things could have been done better, but we can tell that about every sci-fi show. I do not talk about Crusader or most of the silly movies.
It was an experiment to slightly plan forward 5 Seasons of story and holding that promise, unveiling things which were planted seasons before. Some things of course did not work without some patchwork, like the unexpected change of captains and their meaning being "the one" in season 2/3.
You do not have this in DS9 until S3. (I love both shows)
To the question, which came first: It is very likely that Paramount used Straczynski's ideas to influence or even develop DS9 (since they had his first 22 episodes as writing already in '89), however Straczynski never wanted to sue them. You can read about that on wikipedia.
Scientific ideas about how ships, stations, weapons, governments and societies work were very well made in B5. The choice to focus on 4 races was a good one. Of course, it was heavily LotR influenced storytelling, but it worked out.
BSG on the other hand was sometimes terrible to watch - too much obvious but claiming-to-be-very-philosophical dialogues (the philosophical questions thrown up in a sci-fi-show should be between the lines), too much new age hypertheories, terrible nausea while watching space scenes, and again only a few actors were good - however none were as terrible as some in B5, I must admit.
BSG deserves its credit to be a fine show. But it does not deserve to stand beside Firefly, Star Trek or Star Wars at all. B5 in my opinion does.
I would add it to the second bestest, where Stargate Atlantis, Farscape, Earth2 and so on can be found.
Well and there is Andromeda. We can agree about that one, I hope.