You're only using 2/3 of the spectrum, compared to built-up areas where were using all of it many times over, I think you're fine.
As for Bluetooth, I did a quick Google refresher and came up with the following:
Bluetooth utilizes frequency-hopping spread spectrum technology to avoid interference problems. The ISM 2.4 GHz band is 2400 to 2483.5 MHz, and Bluetooth uses 79 radio frequency channels in this band, starting at 2402 MHz and continuing every 1 MHz.
I also see mention that WiFi inherently listens to see if anything else is transmitting before sending packets, so it should just slow down if bluetooth is active on the same frequency, although from what we can gather above there should be plenty of bandwidth outside of your WiFi channel for bluetooth to function on anyway.
Bluetooth is more likely to glitch if doing heavy data transfers over 2.4Ghz WiFi, from the same device you are sending/receiving Bluetooth to at the same time.
