Those board sizes that are being recommended are pretty big for your weight. What you also need to take into consideration is that you're most definitely going to be on a wide board. A wide 158 is going to support a higher weight range than a regular 158. So with that said, doing a 164 wide is simply going to be a tank for you. If you're focused on powder or pure freeride, that's actually a good way to go. But for any freestyle or tight turning, you're going to have to put a lot of effort into it.
At your weight, I'd place you in the 156-160 range all in wide. If you're interested in Never Summer, the Proto CTX in a 158 would be an excellent size for you. It also has blunted tips so the board will actually ride like it's a bit longer. You could even move down to the 155 if you want more playfulness.
The difference between Never Summer's and Lib Tech's profile is the placement of the camber zones and the amount of rocker in the middle.
Never Summer places their camber zone just outside of the inserts. Lib Tech places the camber under the inserts. So with Never Summer, the camber doesn't really kick in until you initiate an edge. With Lib Tech, you feel the camber at all times, but because of the rocker in between, the board remains more playful than a full on camber.
I will say that the NS will have a steeper learning curve coming off a traditional camber just because it's going to feel loose when you're not on edge. Carving on an NS should feel familiar though so don't hesitate to lay one down like normal.