Prostate-friendly Saddle and Sitting Angle
My scrotum (pardon my french) prefers this style of saddle:



I also tried this, but didn't like it. It seems good on paper, but my butt always wants to slide forward, plus not being able to squeeze the saddle between my thighs when going over obstacles means less control over the bike.



Anyway, your best bet may be a recumbent bike. I have one, the big drawback is that it climbs hills like a brick, but comfort is perfect.