I got, , before the company went under, grip shapes, from 'off the front'

they are lumps to put under the tape, with enough of them,
created a flat area on the tops of my randonneur bars.

The broad surface helped a lot..

now you may have to make your own ..


fwiw , Used Grab On sleeves on my touring bike in the 80's,
but they are a PIA to try to pull on over brake cables on aero lever brake

then a couple layers of padded tape would do fine.