The top edition already is $1700, the cost of adding LTE must be a pretty small fraction of total cost at that point.
For business people your arguments 2 and 3 are actually incorrect: I don't want to use my personal data plan for my work. If the device has its separate LTE, it can just all go to my company and I'm done with the costs.
I actually think 3g on tablets is rather silly now. With basically all mobile phones having the ability to share internet, why do you need to pay additional money for another mobile plan...
2) It would cost money to add the device to your Mobile account
3) You can just use the mobile hotspot feature on your phone and connect through that. Its easy on my Nokia 928.
Hell, half the time I have my wife's iphone connected to my phone via WIFI because she has AT&T (for work reasons) and they suck most places we go.