Most architectural prints look cheap for one reason: people stand a column on a 12 mm base and wonder why it tips at layer 40.

Put the largest face down. Add a 5 mm brim, not a raft. Rafts scar the stone texture you just paid filament for.

Marble PLA does not hide a 0.28 mm layer height. Drop to 0.16–0.20 mm and keep 3 walls. Infill can stay at 15%. The eye reads walls, not gyroid.

If the first layer shines, your nozzle is too close. Stone-look filament shows ironing and over-squish immediately. Back it off until the texture looks matte, then leave it.

I keep a short pack of print-ready capitals, rosettes, and garden fragments for FDM machines. If you want a second pair of eyes on a printer that will not stay calibrated, that is a separate 1-hour session — not a forever support ticket.