You can never get to “fully 3d printed” unless you can print metal, and even then the tolerances just aren’t there yet.
But if you want a 3d printer that’s as 3d printed as it can get, why not look at things that were designed for it, like Rook or Mulbot or The 100?
IMO, you didn’t get unlucky with the K1M or lucky with the P1S. That’s the normal state of printers. Most printers are hard to dial in well, and the Bambu printers work like a dream out of the box. Luck is involved for anyone that didn’t start in those states.