My venture into the world of 3D printing has continued with more learnings.
The top surface will almost always look the best, so "put your best foot forward" by putting your most important surface on top whenever possible.
Curves on the top can be weak, it is a good idea to thicken then whenever possible, or rotate the object so that the round part is not on the top surface.
Tool path matters, and can make an ugly trace that is hard to file off.
Rafts and supports pretty much suck. This may just be my opinion, or maybe I'm just too inexperienced to appreciate them. But when I first learned of this feature, I was under the assumption that they would be easy to remove, like a quick snap off, and was really impressed and excited to use them. After using them pretty extensively for some designs, I've designed that not only are they a pain to get off, they leave impressions on the piece that would take forever to sand off, and can damage the piece itself. Also, the software that I'm using doesn't give an options around them, they are either on or off. So if I need supports for a part of the object that starts a little ways off the table, that means that EVERYTHING gets supports whether or not I want them. The lesson here is do everything possible to design your piece in such a way that it needs neither rafts nor supports.
Switching filaments during a print job is awesome! The printer I was using had just started a sexy 8-bit bow tie when I realized it was printing in silver and not in white, like I had planned. Whoops! Luckily, it had only laid a layer or two, and I thought, hey why not, could be cool with some silver on the back. I paused it and changed to a white filament and continued the print job, which all went very smoothly. Then as it started building the raised section of the bow tie, I realized it would be swell to make that a different color too, like black. I paused it again, switched out the filaments, and voila! I even had a young admirer look in awe as my printer seemingly printed with two colors! When I brought the piece home, I was asked if I had painted it. All I can say is, it looked good, and I'm so happy I decided to do the black, because all white wouldn't have been nearly as cool. A hint to anyone trying this: The printer doesn't pause immediately when you tell it to, it finishes out the layer or section that it's on, so make sure to pause it earlier rather than later. I came up with the idea after a couple layers had already gone on, but one would have to look really closely to see the white in the mostly-black section, so it doesn't have to be terribly precise (unless your piece requires more precision). Also, the silver is barely noticeable unless you actually turn the piece around in your hand.
Expanding on this idea, I feel like it might be possible to actually have two (or more) separate jobs. As long as the pieces fit together on the software, in theory, you should be able to tell the printer to print the bottom part, then switch the filament, then print the other sections before removing the first piece(s). I can't imagine I'm the first one to think this, I guess I just don't see a lot of material on 3D printing techniques, but this should be one of them.
I think that's about all for now, but I'm sure there will be more to come as I continue to push the limits of 3D printing with my untamed imagination!