Wasnt part of the change in 11 to make the menu smaller? it seems they just keep adding things back. How can I remove any of it?

And potentially risk those 100 PCs getting errors when trying to install updates and space is low. Are 7GB worth that much in 2025?

Promising software. Acceptable bug mitigation. I'm liking it.

Windows works fine unactivated. It just can't be easily customized.

Why? Windows Sandbox is Hyper-V at its core, just doesn't have all the management tools installed. (Virtual Machine Platform is a required feature, that's Hyper-V's core.) If all you're wanting is a disposable container, going full-on Hyper-V is just making it needlessly extra complicated with no gain. Sandbox is quick to start and resets itself on close, zero mess or fuss. Of course if you actually need the full feature set that's something different, not knocking Hyper-V as I got a few machines running most of the time myself (plus WSL2 and Sandbox), it's a really good hypervisor. Note that yea Windows itself might take a small performance hit, never really noticed it myself gaming and such but your mileage may vary with the hardware. But per Microsoft, Windows still has direct access to all the hardware, GPU included. That said, if it's a concern, might want to switch to a type 2 hosted hypervisor instead for the VM's, say VirtualBox and the like that isn't bare metal.