I will second the drying filament statement. It’s genuinely shocking the difference it can make. Pretty much every metric is improved by using properly dried filament.

There are also food dehydrator mods out there on thingiverse/printables to convert a cylindrical dehydrator to work for filament without butchering the stands that come with it. Plus side is you can also make beef jerky with it :P

I don’t think the tolerances would be too bad. A lot of prints that have tight tolerances have a test piece that you print and test against a known object, which let’s you adjust your print to get tighter tolerances. Once you correct for the expansion of the plastic, getting the right tolerances should be totally doable.