Stargate: Universe. I never got into Stargate before, and I really liked what was going on with Universe. Longtime fans didn't. Though, after going back and getting into SG-1 and Atlantis, I very much understand why they hated Universe. The original shit is so much more fun, where Universe was overly serious. I still like the concept, but I think it would have been way better with the campyness of the original shows.
The second is Limitless. It was really fucking good. It was constantly pulling me in. And they cancelled it because too many people found it to be "unrealistic." I'm sorry the show about a neutropic drug that makes you into a super genius isn't real enough for you.
SGU was a soap opera in space. So much drama between the characters instead of an outside force much of the time. SG1 was mostly focused on the SG team working together against something external like the goa'uld. Very rarely was there anything other than comradary or in jack and sam's case, romantic feelings and/or sexual tension. The chemistry between the main cast was great. SGA had some degree of intracast member tension but by and large they still worked together well. SGU had a lot of mistrust between Rush and everyone else and for good reason. He was an arrogant dick that put his own interests above others a lot of the time. Keeping secrets from them and generally being unlikable. Eli's arc was just sad. He was away from his mother who later became ill, watched the woman he had a crush on choose someone else and had to personally sever the connection between him and his new romantic interest to save Rush then if that wasnt bad enough, we dont know what happens to him after the finale. SGU might have been ok and I stress ok but not on par with SG1 or SGA if it was a completely separate franchise but alas, it was part of the same franchise and there was no justifying that it held its own against the others.