Actually, I think the "rule of thumb" came from this scenario. If you can comfortably put your thumb (sanitized, or course) in the wort, you should be good to go.
I just finished up fermenting my first batch using EdWort's recipe and just left it in my basement for a couple of months. The temp ranged from about 60-70 degrees. Nothing special. It turned out scary good!
The priming sugar that comes with the kit is pretty much the most you would ever need. Here's a good article on how to determine how much you will want to use.
A Primer on Priming
Putting your beer in the fridge for a couple of weeks should help to decrease the carbonation, if it's over the...
May want to think about having it bead/sand blasted. Usually pretty cheap and will get all of the rust out. Then hit it with some picklex or something, just to neutralize anything that might be left.
I brewed one of my first batches on a large wooden deck and after I saw sap oozing and bubbling from a knot in the wood, I decided that maybe I was pushing my luck. I didn't want to cause any damage to my already aging deck.
Just saw in a blog that someone was thinking it was a chocolate stout with some vanilla extract added. I would definitely be curious in trying a bottle. Don't know that I could handle any more than that, but it definitely sounds like a good after dinner drink.