Hi there, currently I'm daily driving Arch and NixOS but I ran Gentoo for a while. If you want a simple and frictionless experience then you're going to want to use the standard Linux kernel with relevant compile flags, systemd init manager (as that's virtually what every other distribution uses) and then ssdm for a display manager along with KDE or whatever desktop environment picks your fancy.
Unfortunately you're missing out on a lot of the benefits of using Gentoo at this point - namely running systemd when you have the freedom to pick any other init system like runit or something else more modern and better designed.
Changing your init system will pose challenges though. The commands for enabling services will be different (which is to be expected) and you might have to install different packages that are say runit compatible as opposed to systemd compatible. All are relatively simple to overcome however this certainly won't be frictionless.
In regards to the other parts its generally all pretty straightforward, you simply install some packages and then enable services with your init system, tickle a config file or two and voilà .
It seems to me you're after Gentoo for privacy and security reasons though. You might be interested to know (if you don't already) that all the binaries from repositories are signed and you can verify them yourself with the signatures.
Furthermore you can also install everything from scratch on any distribution. I'm sure I am patronising you but its something to think about.
Gentoo's documentation however is superb so give it a good read. Mental Outlaw has a good video on installing Gentoo and I believe Luke Smith does too.
Any questions feel free to let me know, I'm more than happy to help out :)
