Did you ever choose a tablet and try it out? I'm trying to decide which tablet to get before I get the MobileSheets Pro app. I am currently looking at an ASUS ZenPad 9.7" but I expect the 10.1" would be better, of course.
New Google's Pixel Slate tablet can run Android apps. 12.3" 3000:2000 display, 12 hour rated battery life with quick charge. Pencil optional. Less then 1.6 pounds (731g) and 7mm thick. With fingerprint sensor.