Many years ago I read an interview from a former escort. She said that many hookers would go out of business if the men's wives or girlfriends knew how to give great blow jobs with swallow like providers do. That is on a regular basis.
Here are activities that I enjoy but would never ask my wife to perform for fear that she would find them too gross or would not ask her to perform out of my respect for her:
1. TUMA = tongue up my asshole. The first time I had it performed it felt a little weird but now I really enjoy the added sexual stimulation. This is very commonly provided by Asian providers.
2. Rusty Trombone = she performs TUMA while she strokes my erect penis to pleasure me on both sides of my body. This feels so good.
3. Going Greek since my wife's asshole is too small to even try. She would get weird with that too.
4. Blow job with swallow since my wife thinks swallowing semen is disgusting.
5. Cum on face since my wife finds this disrespectful and nasty.
I am sure that many hobbyists and providers can add specific activities to this list.