Fails as Drama? ... Nope. Sinclair was AWESOME. Sheridan was, but not nearly as much.
Fails as Science Fiction? ... Hyperspace, aliens with actual alien cultures (no seriously, Narn music?! GAH!) ships and stations that only have gravity through spinning sections and, of course, Time Travel.
Fails as being hopelessly derivative? Well, all fiction is derivative. DS9 was derivative, especially given that they took three TNG characters at the start (Miles, Keiko and Molly) and another few later on (Worf, gowron), and basically built upon what came before, and of course had various derivative stories that was episodes from TOS remade (TNG even did that in its first season, The Naked Now! or Time? I forget which was TOS and which TNG)
I dont like TBBT for the simple fact that, if you watch it without the laugh track, it's... not actually funny. There's "Without the laugh track" edits on youtube.
https://www.youtube.com/watch?v=jKS3MGriZcs
(how do I embed?)