Linux

I am looking to set up a computer for someone switching from win10 that wants to remain dual boot for a couple niche apps.

I want to set them up on something that is debian based, and likely semi-annual release schedule so it's frequent updates but not rolling release bleeding edge. My initial thought was kubuntu. I can disable snap or educate them about package management, so the snap ecosystem controversy isn't too concerning to me.

They will be using this system for "normal" computer stuff... libre office, web browsing, instant messengers, and some gaming (mostly Steam). Currently using an nvidia RTX 2060... but this could change in the future. They've tried live usb of several WM's and want to try KDE (plus they have a steam deck and want to learn how the desktop mode functions better).

My questions are these:

1. Are there other distros to consider that would fit the description that might be better than *buntu these days that meet the above requirements?

2. The plan was to have two separate SSD with their own EFI on each and using the uefi interface to be the boot loader. I have heard that some debian based systems, particularly *buntu, have a bad habit of trying to grab whatever it thinks is the primary EFI and write to that regardless of what you tell it to do during install or on updates. Definitely want to avoid that because rebuilding GRUB or fixing boot issues is just barely in my wheelhouse and definitely outside their wheelhouse. Is this still an issue? Are there fixes to prevent this? Looking at other distros was partly because of this but I don't know how pervasive a problem it is.

Thanks in advance. :)