Windows 10 was designed to be able to switch between desktop and tablet if a keyboard wasn't attached (and most devices do - except fixed laptops without some fiddling - most don't have touchscreens though). My laptop also came with integrated biometrics (fingerprint scanners) and it's unlikely to buy a computer without a webcam - you can use parts of the data for making biometrics but shouldn't use all and will have to keep it stored as normal biometrics now use pattern matching so the data can change quite a bit while still being accepted (like putting your finger on a slant).

Completely filling and rewriting the drive would work but would also be intensive. I don't think encrypted folders are yet a thing anywhere (they might be) but there might be a way to add an application that's able to encrypt and decrypt the data along with it to resolve that - there might be ways to hide this information in unsuspecting files to further hide it (so you don't have a bunch of dot dats and malware heuristics don't find the files easily)

I'm sure there's a simple program to takes the last few microseconds/milliseconds of a timestamp and presents them as a random number (it's something that could be tested and would work with other things too).

Blocking peripherals is a hard task, especially if you want your keyboard, mouse and biometrics to remain and some devices could disguise themselves as that - you might be better off using an open source VM for this, controlling the clip pard and limiting Internet access - it's much easier to guarantee if it's segregated.