Feedback on the Lenovo ThinkPad X1 Extreme

This question was expired because of no activity for 15 days. I am offering my help to make sure this hardware can be considered a good platform for Ubuntu. I consistently have issues like not being able to come out of suspend state, not being able to hot swap monitor configurations (unplugging is generally ok, plugging in is not as successful), recovering from unplugging the ThinkPad Hybrid USB-C with USB-A Dock, latency using a Logitech MK710 cordless keyboard/mouse. I can go into more detail, but only if someone can actively work with me.

I am having issues getting in to Plasma when I get these messages logged:
[ 1.523001] CPU4: Package temperature above threshold, cpu clock throttled (total events = 1)
[ 1.523013] CPU10: Core temperature above threshold, cpu clock throttled (total events = 1)
[ 1.523013] CPU6: Package temperature above threshold, cpu clock throttled (total events = 1)
[ 1.523014] CPU0: Package temperature above threshold, cpu clock throttled (total events = 1)
[ 1.523017] CPU10: Package temperature above threshold, cpu clock throttled (total events = 1)

as well as numerous errors like this:
[ 2.075754] PKCS#7 signature not signed with a trusted key
[ 2.075770] nvidia: loading out-of-tree module taints kernel.
[ 2.075774] nvidia: module license 'NVIDIA' taints kernel.
[ 2.075774] Disabling lock debugging due to kernel taint
[ 2.078772] nvidia: module verification failed: signature and/or required key missing - tainting kernel
[ 2.114383] nvidia-nvlink: Nvlink Core is being initialized, major device number 238
[ 2.114822] nvidia 0000:01:00.0: vgaarb: changed VGA decodes: olddecodes=io+mem,decodes=none:owns=io+mem

I don't need high performance graphics, just the most reliability I can get. I had been using graphics in hybrid mode, but am really looking for the best configuration choices to make. What BIOS should I be at? Do I just grab the Ubuntu Nvidia drivers for 430? Do I use nouveau?

The https://certification.ubuntu.com/hardware/201809-26479 page shows "preinstalled by manufacturer", but Lenovo told me they don't support Ubuntu. Is the manufacturer "Ubuntu" in this case, or Lenovo? I'd love to help get this thing completely certified, if you'd feed me some information, like what the proper BIOS level is, and things like that.