That's great to hear she's keeping her hair healthy!
For me, there are two mane hair sensations I love.
The first sensation is her hair brushing/dancing across my skin. It's light and tingly and soft. If she does this to my face, it feels like a little orgasm because it makes me shudder. But I don't think I could have an actual orgasm based on brushing alone (though I am willing to try in the name of hair fetish science).
The second is her hair wrapped around my cock, which is more of a slippery feeling, almost like if you or she grab your cock through a couple of layers of a silk, satin or nylon fabric like a nightgown. Someone once described it as the feeling created by individual hairs rolling over each other. This feeling makes me cum like crazy!
Everyone is triggered by different sensations, and if your trigger is wet softness, great for you. Maybe a shampoo hairjob would work. Then, you could cum right into her hair without creating the mess that some women don't like.
Cheers!