When are you going to stop running Prince? Spikes ahead slow down, chill, and drink that potion. I'll hack the hour glass time for you.
From my experience testing MultiOs Boot 98SE, XP, 7, and 10.
People are correct that you get a bunch of defaulted to YES options for sending information to Microsoft on Windows 10. There are some others not in the setup process as well that you have to disable. Tin hats or what not it's still a bit invasive and could have been resolved by being defaulted No to all of those questions. Even testing out an internet unplugged W10 machine you will constantly get pestered to update versus Windows 7 where I've tested for a few months of not activating it still functions without the constant update nag pop up windows.
The only true asset to Windows 10 vs 7 that I can see is DX 12.0 for high end graphics cards. It is also a little easier to hook up CableCards to Windows 10 if you are a DVR user. But for the most part Windows 7 64-bit does everything you'll really need with Windows XP 32-bit to run probably 95% of all Windows software that exists. DOSbox would probably take care of 95% of the DOS based games on modern machines.
When it comes to Skylake and beyond.
Windows 7 has issues installing from USB devices which is what you are trying to do. You'll have to patch it so it supports USB 3.0 drivers so more steps are required to get this result. As for Windows 10 it works from the optical disc out of the box and the USB ports function without issue. It might work from off a USB device but I haven't tested this. So even USB optical drives will not work for installing Windows 7 without modifications to the ISO. As for XP you'll have to get a modified SATA AHCI XP driver and you can only install using a nLited optical disc. USB installing for XP is not possible anymore due to the xHCI USB 3.0 ports are non functional since Intel never created an official xHCI XP driver and thanks to Intel they also nuked the eHCI USB 2.0 backward compatibility out of them so you have to get a USB 2.0/3.0 card with XP driver support. Yes Intel and MS truly want to kill XP off but we won't let them. 😀