

UniFi seem to have dabbled with 2.5 GBE briefly and then jumped to 10. I’m guessing that 10 will be the way to go.
You’re looking at cat 6A patch leads rather than 7. 7 requires different but RJ45 compatible connectors, I believe. Yes, I’m still trying to understand what the difference is.
I have a 2.5G router, the CG Max. A 1 G switch (waiting for a reasonably priced 10 G) and a 10 G WAP. It’s a bit of a mess!
Debian Developers are prone to add their own bits with the upstream package. Sometimes it is very useful, sometimes not. They add the relevant systemd units in and turn them on for you and also set up the cron jobs according to which dev prepared the package.
You don’t have to install systemd with Debian (I think?). The row when systemd started to gain traction and DDs debated its inclusion for ages lead to a strange set of decisions, IMHO, about the filesystem layout, which is quite different to what a systemd person would expect, to make it work with the other low level system that is being used.
I thought I saw that sysv stuff is being marked for being removed from the kernel at some stage. Am I imagining that? I don’t know what the alternative init systems are now.
Anyway, Debian is a fine distro.
Suggest you run a desktop with prioritised apt-pinning on Testing and Sid. It makes it semi-rolling and it’s stable as anything. The community makes sure that less than an hour goes past before someone posts a solution to a package error and for that reason I suggest that you always install the apt package scripts which provide the change logs and known bugs with that package before you hit install.
The feedback from the community upstream to the DDs is amazing.
I hope aptitude - an apt TUI - is still being used as that’s one of my favourite ever Debian utilities; a lot of the packages show as hard dependencies when you install them individually but are actually covered by other packages already installed; you can reduce the unused packages in your system by marking the packages auto installed yourself in aptitude very easily. There are several other packages in the repos to do all manner of interesting things. The community spirit is very very strong.
Good luck and have fun.
I found that starting with a debootstrap minimal install from a live distro (I like ArchLinux as a rescue usb, but there are plenty of others on distrowatch.com) and adding a kernel was the best way to go to try to keep the numbers of packages down in my Debian systems. YMMV. My experience was coming up to a decade ago now though, although lots of hardware vendors always love their Debian; UniFi was a Debian fan last time I looked at the controller.