I mean, it just comes down to OS at that point, yea? Why not get a turbo-thin ultra book and throw Ubuntu on it, then use cloud storage for everything? Could just SSH in as well.
You could even install ubuntu on an android tablet.
If what you want is the form factor and speedyness of solid state everything, you could get a tablet that isn't an ipad. Lenovo makes some that would be trivial to swap out for Ubuntu or whatever https://www.lenovo.com/us/en/tablets/c/TABLETS
A big part of it is the zen. I love Linux and it powers my entire career as a server OS but it is anything but zen and I would never use it as a desktop OS.
You could even install ubuntu on an android tablet.
If what you want is the form factor and speedyness of solid state everything, you could get a tablet that isn't an ipad. Lenovo makes some that would be trivial to swap out for Ubuntu or whatever https://www.lenovo.com/us/en/tablets/c/TABLETS