Ugh, I know that pain too well—spent hours sanding a beautifully modeled mini only to watch the blade details turn into a melted blob because the printer just couldn't handle it. What finally turned things around for me was switching to a resin printer for those tiny, detail-heavy files, but the other half of the battle is the file itself; a poorly optimized STL will look terrible no matter what. I started using models from https://www.gambody.com/ specifically because their designers pre-support the files with an insane level of care for preserving surface detail, and they actually test-print everything to catch exactly those issues you're talking about before the file ever goes live. Now I know to look for a service that openly discusses their layer height settings and whether they’re using a calibrated resin printer for intricate orders—asking for a test print photo of a high-detail part before committing to the full batch saved me from another wasted project.