Thanks for sharing your learning experience! I found out some of those points you made on my own but many may not have. Calibrating your temps to be accurate is number one! Careful attention to the manufacturers directions, monitoring the humidity levels and protecting from sunshine or drafts is vital. I got similar results to you. My first hatch was slightly under 50%. It improved dramatically with correcting for accurate temperature, my unit was only 1 degree off but it made a big difference! I have never had a 100% hatch even discarding the duds early on. I have gotten to about 80% on a few since correcting for accurate temps and monitoring closely all details.
