Exposed to sunlight, every tablet's screen is useless. That is, until they adopt S-Amoled technology.
Weight: it's a 0.5 lbs difference between the lightest and the heaviest tablets (according to Gruener); half a pound will really break your hand? In that case, you need to put the tablet down and go to a gym. Really.
Of course it's not a notebook; none of the tablets is. This should be a "negative" point in reviewing any tablet, not just this one. You get a tablet because you don't need a notebook, given the circumstances, not because you are looking for a replacement. If you are, just get the damn notebook and be happy. This "downside" is a moot point.
The price of 4G: this is shameless carrier pricing, and I don't see how this is a tablet's "negative". There are plenty of tablets out there without the 4G experience, and if you think a 3G suits you better, go for it. Same goes for a Wi-Fi only tablet. And again, nobody puts a gun to your head to get the 4G working; even if it's available, you can always turn it off and use the Wi-Fi option only. At least you have the option, most tablets do not offer that. I would see this as a positive.