I'd like to add my 2cents! I commend you on the great work you've done....I had my vent hood set 20" above my torch so 24" from the table top is about right. The big concern that I have for you is your carpet. I often have shocky glass.....I covered my carpet with plywood. When you're lampworking your focus is on what's going on in front of you, obviously. So you don't need to be concerned about tiny sparks that possibly flew off! If you're renting, this is going to also be something that you want to protect for that reason as well. (I originally was using my gameroom for a mixed media painting studio, so I covered the carpet with plastic, then the plywood because I literally threw paint). Also, be sure to have a fire extinguisher handy. Sorry but I didn't notice if you had one.
Happy creating,
ginger