Initially I wanted to provide a somewhat generic but trimmed kernel
but this was in poor taste. If someone wants a pre-configured or
pre-built kernel they would be better off using something other than
Gentoo. Much like vimrc's and emacs.el's you are far better off making
something yourself in most cases.
As a user, if you aren't familiar with building a linux kernel you may
be better served by using the defconfig and recompiling as needed,
since you would need to spend some amount of time learning about your
system and the features in the kernel.