Yes, you change your DNS settings so that your domain points to the new provider servers and recreate your email addresses there. You won’t have the old emails unless you backed them up and restored them but the address will be the same.

I bet on more cooling due to shorter layer time in that area. Maybe the fan is blowing harder, check your cooling fan settings, and minimum layer time.

Been using my domain email more and more for that reason, and the setup with Proton was quite easy, integration is great too. I even set it up with Pass to generate privacy aliases on a subdomain of my domain.

You can create a full color 3d model of the helmet including signatures by using photogrammetry. A phone is enough to do it, there are even apps that do it for free. There are also desktop apps that are open source that can do it. Color 3d printing is also possible with technologies like HP (Multi) Jet fusion. Hobbyist are unlikely to have them but a maker space might.