The other ergonomic item that popped up on my trip from CA back to Missouri was the stock Harley grips.
This is a individual thing, but I liked the OEM grips for a few hours, but after a 400 mile day, they were letting a mild buzz through the grips.
I have always used the Kuryakyn grips & liked them, but after researching replacement grips, this pair rose to the top for quality & price.
Avon Velvet Air Cushion Smooth Grips For Harley. For newer models, you need the fly-by wire model & I chose anodized black & the difference is truly amazing for me. On the Freewheeler, even after extended saddle time, you feel no buzz, tingling or anything bad through the grips. Nothing but pure comfort.
Revzilla also has an excellent video on changing grips, both cable & fly-by wire.
Here are before and after picks: