Can’t speak to 3.14 not being available, as I use 3.13 and 3.11 here myself.
For most of my stuff that requires anything there isn’t a package pre-made for, I use venv. But as you noticed, dependencies not being found can be an issue - you have to install those packages on the host (you need the relevant -devel packages). You’ve probably noted that if you try to build/install packages with pip outside venv, you’ll get a message that you may create issues by installing using pip when there’s system-managed packages. That message is accurate - using venv (regardless of OS/distro) is highly recommended.
If you provide specific examples of what you’re having troubles with, someone may be able to assist. I’d probably start by making sure the base development pattern (devel_basis) is installed, but what’s going to be required by any given python library is going to depend on the library’s requirements itself - there’s no easy ‘you just need these 6 packages for all python package builds’ solution.