Ok, I gave it another shot and here's what I found.
Turns out, that for some reason, huion drivers are conflicting with windows ink. Reinstalling and updating didn't help, so I tried disabling Win Ink. Interestingly, I noticed that the pen started to run smoother, without any stutters. Still I didn't had a pressure of course as I had everything setup with Win Ink as a controller. Changing back to win tab fixed the issue as expected, but now I had to actually do it in affinity.
I tried High precision at first as its only problem was trying to kill my pc every 5 minutes, but this time it works without a hitch. Just out of curiosity I tried Low precision, but that one still have produced blobs whenever I tried to draw rapidly.
So in conclusion, whe one day you'll wake up and notice that your pressure has thrown a tantrum, just turn off the Windows Ink in drivers and use High precision as pen pressure. It helped me for now, we'll see how long it lasts.
Also @Callum, sorry for pinging, but do You have any updates on the "blob issue"? It would be nice to use Low prec instead of High, just in case High decided to blow up again.