Hi BennyOrbit,
I love the 1' Nalu, currently my fave board. The 11' is forgiving, and easy to paddle but still has performance to burn on a wave. Irode it every day whilst up north on waves from head high to waist high. I was demoing all the range that week but I always found myself wanting to get back on the 11'er, which I did

The 10'10" is a nice board too, however, it will leave you wanting more for surfing whereas the 11'er will allow you to grow. It requires a bit of old skool walking or cross stepping for perfect trim and nose riding, and a quick step back towards the tail pad will crank a nice turn turn back to the peak into the pocket. Biff off the foam ball, a quick step forward to trim for speed and repeat. Can't get enough of this!
The width of the Nalu 11, will make it easy for your significant other or yourself to paddle flat water and not be thrown off by the odd errant wave from a boat. If the budget will extend far enough, I'd definitely go the GT construction over the GS as the weight saving, premium fins and premium deck grip are worth it in my opinion.
Either board will be fine, as you suggest, but the 11 foot Nalu in 2015 shape is a real keeper.
DM