(IANAL, not your lawyer, this isn’t legal advice. Heh.)

I personally am a huge fan of copyleft licenses. “Copyleft” means that the licence is permissive in that it allows, for instance, redistribution (sharing) and derivative works (remixes, mashups, etc) but only on the condition that if they share the work or any derivative works, they must do so under the same license terms under which they got the work. That ensures that a) no one can (legally) make a derivative work of your work and put it under a more restrictive license and b) if they publish improved derivative works, you can take those improvements and incorporate them into your work (and the derivative work publisher can’t object – or at least doesn’t have a case if they do.)

In terms of Creative Commons licenses, “share alike” means “copyleft.” (The other popular family of copyleft licenses is the GNU GPL family of licenses, but those are really more designed for software/code than non-code works. Even OpenSCAD models, I tend to release under a Creative Commons license rather than a GPL license. Though for other, non-3D-printing works of source code, I always use the GNU Affero GPL.)

Aside from that, I tend to go as permissive as possible.

So, in concrete terms, for 3D printed models, my go-to license is the latest version of the Creative-Commons-Attribution-Sharealike license. This ensures I get some credit down the line and ensures nobody can make a more legally-restricted derivative of my work. But it also explicitly allows the creation of derivative works and even sale of drivative works under the condition that a) I, the creator, get credit and b) the buyer gets the same rights to the work.