Well... what I would do and what I think that you should do are hypocritically different.

I'm sure I'd allow my heart to make the decision, but of course my advice is to listen to your head for now.

You've listed the attributes that your friend has that contradict what you consider your criteria for a long-term partner. Your criteria are smart, IMO, not overly picky or limiting. If your friend doesn't meet those criteria, then it's much better to stop now before you fall too deep... but then again, it's much easier saying that from the outside than to be in the situation.

I have a feeling that you'll do what's best. You seem very grounded to me.