DR FJL, I think you're totally missing the point of UGLY BETTY.
It's a BROAD American version of the Mexican telenovellas in which there are stereotypical characters of every persuasion.
If you think Marc is so objectionable, doesn't that mean that you also have to think Vanessa Williams (and all powerful black women) are objectionable, and Eric Mabius (and all spoiled, pampered rich white men of privilege) are objectionable, and , well, you get the picture.
The show is a comedy which pushes buttons on all races, classes, and sexes. What I have admired greatly about it is that Marc, and Vanessa, and Eric's character have all shown moments of great tenderness, generosity, and warmth amid their devious, often self-immolating ways, and the fact that you can find these things in a broad satire of Spanish soap operas is quite wonderful.