Eric. I think a lot of the problem is we have few of the classical amateur designers coming through with real hands on engineering experience using 3D printers. So many are blinkered that if it is to be 3D printed it must all be 3D printed. Until recently a lot of people failed to understand grain in printed parts, and that you should mix and match parts. PLA doesn’t glue well, but it welds great. It really is a case of understand the materials and their limitations, then work within them. A lot of the free library sites are full of rubbish that people tend to print because they can, not because they should. You then have the situation where the majority of stuff you see printed online is just crap. I mix 3D printing in with my everyday designing and prototype work. Sometimes things don’t work, but you shouldn’t look at it as a failure, just another step in the right direction. If you have any design abilities I would recommend a cheap printer to start with. My printers were all budget models and I just adapt them as I go along. You never stop learning, just as you do any machine tool, think of the 3D printer as another tool, not a complete solution.
I’m still learning Eric, I have used lathe and mill far longer, but the 3D printing just clicked with my level of engineering and craft skills.