I started to not scrape or wash the dish I use to freeze the solvent initially. Although, I am sure some impurities are still on there, it seems some goodness is too. Since I use Naptha that is warmer, most of the stuff seems to melt pretty quickly and it seems to work better...I am getting more crystal formations. Is this safe too?

I think temperature, time and amount of product in solution are more likely to influence crystal formation personally.

If you don’t clean your tools properly I suppose you will be adding oily crap back into your next pull and you will also be leaving stinky containers lying around.