An example of over focus on one supporting character (for me) is ST TNG's "Nemesis. I loved TNG, but I haven't seen Nemesis since the theater, even though I have it on dvd, because I couldn't take another Data heavy story. I even hated the ending, because it WASN'T the big emotional tear jerker like the end of Wrath of Khan since they already provided an alternate Data to "carry on".
But that one was retarded! They mothballed him!
I'll admit to being beyond meh over Data's sacrifice.