in lenses for the T2i is not too significant and you want to record audio internally, then perhaps a look at the Sony NEX-EA50UH... because of audio. Large sensor, interchangeable lens system, and two built-in XLR inputs... and a hot-shoe for dSLR flash use and a a cold shoe you can install for other stuff like a video light, wireless mic receiver... and a slide-out shoulder mount( seems a bit chintzy but the eyepiece seems to fit well...
If you choose to deal with camera-recorded audio, then you probably will need a XLR adapter (this would impact all of those on your short list with a 1/8" - 3.5mm - stereo audio input. And the good shotgun mics need phantom power, so be sure the XLR adapter has that option (the EA50UH has a switch for each channel in the audio control area on the left side of the camcorder).
The EA50UH is similar to the FS100U (and the only one on your list with XLR inputs). The imaging sensor's are different, the shoulder mount, and the 50UH has an optional high capacity memory unit. When the shoulder mount slides out, there are three 1/4" standard thread holes for mounting even more stuff (and when shoulder mounted, the extra weight is useful for stabilizing.
We presume you have appropriate computer horsepower and hard disc space to deal with editing high definition video and a decent video editor to to the editing...
Granted, I just got an EA50UH and am using it to augment a HDR-FX1 and occasionally a three-cam shoot with a HDR-HC1...
Canon 5D, Blackmagic Cinema Camera, Canon C100, Sony NEX-FS100U, orsomething else?
I currently have a Canon t2i and I'm definitely ready to upgrade to a more professional, larger sensor camera, the question is which one? I need a camera with good low-light, a film-look (would be nice, but not necessary), all-in-one (in other words, doesn't need a ridiculous amount of accessories to make it better), and overall just amazing. I'll set my budget at $5,000. Feel free to offer other camera choices and back up your answers with facts. I'm not a huge tech guy so please don't throw technical jargon at me. Thanks.
I also asked this question here if you would like to post your response there and make my life easier:
http://answers.yahoo.com/question/index?qid=20131209180249AA56XdU

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