I also use the spatula, but the tool I use all the time, even when not using the cricut is the sharp little hook, but I don't know if they're available except in the tool kit. The hook and good tweezers that I got from Avon probably tie as my #1 scrapping tool. I also have SCAL so have never used the cartridges, although I have three or four.
I also use a guide that suggests settings for various papers. Google Cricut Cutting Guide. I think it was about $5 and worth not messing up my paper.
Enjoy! With six kids you deserve some fun