The camping foam is usable and some makers love it. I don't, except for one time use. Even the EVA foam gets replaced after a few uses. I can't abide worn foam. Some people seem to be able to use the same foam for months, but it seems like magic to me how they do it. Kinda like when I read that .060 is easy to work with. .060 makes me question my sanity. I hate it with an undying passion. I'm not fond of .080 either. It's a "milage may vary" sorta thing I guess.
A bit of advice, and I hope no one takes any offense to this. Ignore any tutorials beyond the basic "heat, press" and tips you find that work for you. When I made my first sheath, I had never seen a kydex sheath in person. To this day, I've never handled another maker's work oher than when I was replacing it (factory sheaths or custom sheaths by unknown makers) or when it came with a knife I bought.
My first few sheaths were horrible. They worked, but were rattly and unsightly. I started off with a hacksaw, a manual eyelet setter that didn't fit the eyelets at all (heck, at the time, I thought they were supposed to be smashed and twisted like that.

), and my feet as a press. Even my first sheaths sold were quite bad. I worked through trial and error to a point now, when I think my sheaths are pretty good, but I know that the ones I make Tomorrow will be better than Today and so on. I like to try new things, and I think I'm a better maker for it.
My point of all that, if you've skipped ahead by now, is to keep at it and any kinks will work themselves out in time. Your sheaths IMO look great and you'll find little things specific to you that will make them better and better each day.