I recommend a really cheap wireless keyboard, eg https://www.amazon.com/Wireless-Keyboard-Control-Touchpad-Controller/dp/B08NSXBZ4T Sweat can confuse the touchpad, but the keyboard part never gives me any trouble.
Agreed on the BT mini-keyboard…I put a 1/4 turn mount on the bottom of mine and have it mounted to a Garmin mount on my HB.