71Romeo, I wrestled with this interface issue as well. It seemed, the more I tried to find that perfect combination of gadgetry to make my experience enjoyable, the more frustrated I got. Here is where I ended up........
1. My phone is on a RAM mount and cradle on the throttle side bars. It plugs into the side of the TFT via a Type-C to Lightning cable. It charges as needed when the bike is running. I pair this directly to my Garmin XT From there, I can enjoy music, hear notification alerts, and answer phone calls. The XT is paired to my SENA headset.
2. I mounted a Garmin XT above the TFT display on a Touratech mount. This is my primary control center. I can make music changes, hear turn by turn navigation if I want. (very helpful in urban settings). This is powered via the switched power under the seat. The GARMIN XT updates faster in real time, has points of interest, speed zones, and live traffic monitoring. I think it does it all better than the HD control system.
3. I keep the HD TFT display set up to monitor what I feel is important. (widgets, etc.) In short, the TFT remains dedicated solely to the bike and its functions.
I realize this may be viewed as not taking advantage of the systems I paid for on the bike, but, it makes things really easy for me and I do not have to worry about gremlins keeping me from finding my next destination.
Hope this helps.