Bagpuss
Legend
This one seems more a complaint about the lack of range of female characters on the show, than the portral of any of the male characters.
http://www.ugo.com/tv/11-reasons-geeks-hate-the-big-bang-theory?page=3
Oh so reason number 1 for disliking BBT is the characters on the show are more successful than real geeks, so not at all like every other sitcom (Friends - just how did they afford those massive appartments on their generally jobs?).
http://cliqueclack.com/p/big-bang-theory-hates-nerds/
Ah so this critic is complaining it has gone downhill and become more mainstream, as lost its edge and got lazy in it's writting... okay I can get with it having jumped the shark, happens to the best of them.
http://www.escapistmagazine.com/forums/read/18.304640-Why-do-some-nerds-hate-Big-Bang-Theory?page=1
Ah so the laughter track, not being particularly funny, and getting it's references wrong seem to be the main complaints not how it shows geeks in general.
http://ifanboy.com/articles/199683/
Okay he says he dislikes it but doesn't go into a huge amount of detail, but at least this seems close to disliking it for the same reason you do.
http://forum.the-big-bang-theory.co...ody-know-anybody-that-is-really-like-sheldon/
Erm there seem to be an awful lot of people in that topic saying yes they know people a lot like Sheldon, so I'm not seeing how this helps your case.
http://www.ucsdguardian.org/arts-en...ulture-it’s-just-a-big-bang-bust#.UXLpgMu9KSN
I particularly like how this one while attacking BBT for the reason's you've given, holds The Guild up as a shinning example of how to do a geek sitcom right, despite this being one you attack for the same reason's as BBT.
http://blogs.redeyechicago.com/geek-to-me/2011/12/29/the-big-bang-theory-and-the-nerd-myth/
This one is pretty mixed, and basically points out what everyone in this thread has been saying the characters are stereotypes, but then so are the characters in every sitcom.
And lastly, but probably the best one: http://butmyopinionisright.tumblr.com/post/31079561065/the-problem-with-the-big-bang-theory
I agree it is the best one. Perhaps you should have just stuck with this one. Perhaps BBT has run it's course, I mean there was a time in sitcoms you could laugh at black people, and gays and the like, but that was the first introduction of them into mainstream culture on TV, and as they got more accepted the comedies changed so instead of laughing at them you would laugh with them. Perhaps BBT was the introduction and shows like Community are the next natural progression.
Can't say I'm a fan of the show myself, but mainly because of the canned laughter and it not being particularly funny.