Printing - My First Mistakes

I have a Flashforge Creator Pro that will be used to print my parts. It had been idle for a while and I had to do a couple repairs to get it up and printing again.
First, I had to replace the bed covering. That took a lot of scraping with a metal paint scraper tool and some gasoline to get the glue residue off.
Secondly I had to replace the nozzle because I had damaged it trying to unclog it. It was made of soft copper I think. I bought a stainless steel replacement and that is working great.
Most of the problems so far printing is when the plastic doesn't stick at the start of the print. I've found that that is usually because my plate isn't level or is too low. I tighten it up using a piece of paper. The paper should be rubbing on the nozzle when I have it right.

Don't Forget the Print Settings!
I was so eager to jump into printing that I did not check the recommended settings before I got started. I just went with the default settings in my printer software which was 2 shells and 15% infill. I had 2 broken parts. I cracked the face plate when I snapped it off the bed. Then, my son broke the jaw when he knocked it on the floor. I have already printed many parts, so I will just reprint if and when they break. But, any new part I print will at least have 3 shells and 30% infill. This still might not be enough for the 2 broken parts. The designs are just very thin at the breaking points. I would like to add some reinforcements but not sure which program I should use to do that right now.
Beyond that I probably should print solid parts for anything that has stress. We will see about that later.