Why does my Wacom Cintiq 22HD Pro keep stuttering when I try to render detailed Virgo birth chart illustrations?

I'm pulling my hair out because the Cintiq 22HD Pro (model 22HD‑2022) just can't keep up with the 4096×2160 canvas I'm using for my Virgo birth‑chart masterpiece. I swear the tablet's latency spikes every time I add a fine‑line glyph for the Virgo sextile Mercury—like the device suddenly decides it's a 90‑year‑old CRT.

I've already upgraded to the latest driver 6.4.1, calibrated the pen pressure with the Pro Pen 2, and even switched to a 144 Hz ASUS ProArt monitor to see if the bottleneck is elsewhere. Still, the brush jitter is as erratic as a Mercury retrograde.

What I'm actually trying to achieve:

• Full‑color, vector‑smooth glyphs for each house cusp, using my custom brush set (Bristle‑V2, 0.03 mm tip).
• Layered alpha masks for the planetary glyphs, rendered at 600 dpi for print.
• Real‑time color blending with Krita 5.2's HDR brush engine.

Steps I've taken (and failed):

1. Disabled Windows Ink, forced Wacom driver to use WinTab.
2. Lowered canvas resolution to 3840×2160—still stutters.
3. Turned off GPU acceleration in Krita—no improvement.
4. Tested the same file on a Surface Studio 2; smooth as butter.

So here's the humblebrag‑disguised‑complaint: I spend weeks perfecting these astrological illustrations, and my gear is basically throwing a tantrum. Is there a hidden firmware tweak for the 22HD‑2022 that can handle the insane brush density I'm demanding? Or am I just being a diva because I expect my hardware to perform like a high‑end render farm while I'm only drawing a Pisces‑Neptune swirl???

Any tips, firmware hacks, or even a sympathetic rant would be appreciated. My next piece is a full‑moon Leo tableau and I can't afford another night of lag.