Yeah, I thought of that after I'd posted. So yes, two transmitters and four receivers... there really is quite a lot of wirelessy stuff going on isn't there! I think, though, that we can practically ignore any EMC issues with the WiFi system as it is way up there at 2.4GHz. Similarly I'd not expect the P3i transmission to interfere with GPS reception.
869.4MHz Tx and Rx: P3i
1090MHz Rx only: ADS-B
1575MHz Rx only: GPS
2400MHz Tx and Rx: WiFi AP
All rather fast wiggles for me: I tend to do most of my wirelessry between 1.8MHz and 30MHz!