I design a lot of parts in fusion360 and have been printing for nearly a decade, and even I found some good tips in here.
I would add one very important section here which is filament selection. Modern filaments like PC-CF (carbon-fiber impregnated polycarbonate) are unbelievably versatile for real-world prints and parts, and the higher-end consumer printers can print this (requires a ~300'C capable print head and hardened steel nozzle) with relative ease. There are so many different filaments out there outside the standard PLA that really shine in many ways and aren't 10x more expensive to print with.
Slicers are getting pretty good now too with a lot of work going into slicers to improve print quality, speed and part strength.
Love seeing cnckitchen called out here so many times - such a great resource to follow and learn from if you're getting serious about new developments in 3d printing and unbiased reviews. The quality of models on printables and thingiverse is really getting better and the amount of things you can simply download and print and have a fully functioning device with 0 external parts (print-in-place and single-print components) is really encouraging to see.
Once generative AI gets a grasp on object modelling and cad principles I think we'll see an explosion in functional part models in the same way parameterized models are becoming more mainstream.