I like your glow clip. I would keep it disconnected from the battery when not in use. It wouldn't take much to short that thing out. Things would get pretty hot pretty fast at that point.
Otherwise keep it clipped to something to prevent contact. I have one I keep clipped to the wooden handle on my flight box when not in use.
As far as the needle valve goes, 3 to 4 turns out is probably a safe starting point.