UPDATE 2019-12-29: Re-installed the notebook (needed dual-boot w/ Windows for Bios Update) and everything was working this time without any specific paramater using the same installer ISO (Ubunto 18.04.3)
Unfortunately, i’ve spilled something on my notebook (Skylake HP Envy 13) which lead to an unusable keyboard grmlfpl
I was quite curious about the new generation of mobile Ryzen processors (very happy with my 1.st gen desktop Ryzen), so the replacement is a Acer Swift 3 14 with an AMD Ryzen 3500u (SF314-41-R8HZ), which caused some headache in the beginning as i was not able to boot any linux installer. After messing around with almost every kernel param back from the past (noacpi, noapic, nomodeset) and all other recommendations (rcu_nocbs=0-7, processor.max_cstate=5) it always printed something like nvme ncme0: controller is down; will reset. In the end, it was the WD SSDs fault and nvme_core.default_ps_max_latency_us=5500 did the trick!