I have no interest in a loop for HF but I'm curious as to the answer for OP's question: if he put the loop outside, as opposed to inside, and elevated it 10 feet or so up, would it work better than it does inside?
My guess it the answer would depend on whether he is on a second floor or not, and how much RFI he may need to avoid. At least, that would be the answer for most other indoor antennas (like the indoor wire I use presently).