Anyone using a Konnected alarm panel conversion? How are you getting the most out of it?

I did exactly as you have done. I abandoned my Vista and switched to Konnected. I have been very happy with the change. I use HSM to control my system. I use HD+ to control my alarm system and it works remarkably well. I have several mounted android tablets around my home. And the app works very well on my phone (android only, no iPhone version). Yes, you may have to use RM/webcore programming for specific options (like arming delay with exiting/alarm delay with entering, etc.). I did almost all of my programming with webcore. And there are many examples of RM/webcore code available in the Hubitat/webcore forums. And the WAF has been very good for me. I did build a Hubitat dashboard for her iPhone with very basic arm/disarm options. But we use the mounted pads most of the time. Also, I use voice commands with Alexa for things like "Goodnight" to automate those processes. Yes, initially my wife missed the Honeywell keypads.
honeywell-6160-alphanumeric-alarm-keypad
But pad/phone control is so much better and offers many other home automation options.