Driver sr need updating gentoo
It's also easy to end up with partial hardware support -- perhaps there's a hardware sensor that's available but whose support hasn't been enabled.
How do you know you have enabled everything necessary?
Options for configuring hardware support: are useful and I recommend them if you don't want to bother figuring out what hardware support you need enabled.
On the other hand, I think kernel seeds are an anti-pattern.
This is too time-consuming to do on the 486 PC so I use a modern machine to do the compilation then move the disk over to the ancient PC. I heavily reference official Gentoo Wiki x86 handbook with some tweaks to suit the 486 as well as ease of repeated builds.
Software like systemd requires certain kernel features to work properly.
As a Gentoo user you've probably seen messages like this one: files have thousands of lines.
Criticism welcome :) Advantages of my approach (summary; see below for full explanation): There's no need to duplicate documentation, so go and at least skim through those pages if you haven't read them already. TL; DR: Distros such as Ubuntu and RHEL have their own forks of the kernel (e.g. They also backport fixes to certain "stable" and supported versions.
How kernel development works: https://git.kernel.org/pub/scm/linux/kernel/git/torvalds/linux.git/tree/Documentation/process/2. It's possible to use those with Gentoo, but I fail to see the appeal of doing that.