By the sound of your questions, I would recomend buying yourself a few trapping books. Go with ther modern writers at the beginning as the older books seem to have alot of smoke and wires in them.
When dealing with coon, one must take into account the strength of the critter. Coon are quite strong and if the stake is not sufficient, it will pull it out. I don't know for sure what you mean by steel tent stakes, but it gives me a cold and prickly. (as opposed to a warm and fuzzy)
I use oak stakes 16 - 18 inches long in good soil. I use steel stakes 18 - 24 inches long as well. There are many options but if you are going to be water trapping, you might as well use drowners.
As far as the foil goes, that is a novelty set which you will not stack up any numbers with. Go to trapperman.com and go to the section about basic sets, you will find alot of help there. And register there as well and you can have this site to help you and that one also.
Both traps you mentioned are 2 out of 3 of my favorite traps. You should do well with them.