But the traffic to a combined site will NOT be the combined traffic to the 2 sites now.  

The things that help you stand out are (in no order and not just these items) Location, amenities of the community, size of the community (can it handle the traffic), reputation of community, how well the house is themed (or can be by you).You need to be in a highly amenitized communtiy like Championsgate, Windsor Island, Soterra and several others.

Still if it goes on for hours and hours every day, I'd also start to get impatient-once and a while I get.  

Issues that go into these decisions includes whether the area has adequate power grid, enough water and sewer services, parking, traffic issues, capacity of schools.

However, after looking at the calendars of multiple hosts on airbnb, I got concerned that the foot traffic is a little light in the area.

Did you analyze the traffic through the area or the current operating income?

The house has constant traffic and is rumored to be a meth house by the other neighbors.

.- there would be more traffic and there is a permit to obtain from the County.  

Heavy traffic and road closures, locusts, etc.

Having just sat in very long traffic lines in formerly sleepy Weatherford, I can attest that this area has been discovered.