Out of curiosity, why not just use the built in navigation through the TFT with your phone? I've found it to work as well as any Garmin product I've owned in the past. If I'm using it for directions, I use the TFT for turn by turn and then leave Waze on my phone so I can keep an eye on traffic hazards and speed traps.
For a headset I'm using the Sena 50s. Cardo gets really good reviews too, get the one that your riding friends are using so that you can all use the MESH intercom vs std bluetooth.