I have been fiddling with my old Basso, which is now a singlespeed dedicated turbo trainer bike. (I have virtual gearing available in the smart trainer apps that I will be using.)
I was very uncomfortable testing the setup last week, suffering terrible genital numbing! The main cause of that turned out to be that I had somehow got my saddle over 2 cm higher than usual so I corrected that mistake yesterday, which greatly reduced the problem.
I was able to complete a 1 hour turbo session and had only minor numbing afterwards. That would be tolerable once in a while but I will probably be using the turbo 3+ times a week now until next spring so I would really like to get even more comfortable.
Today, I have been trying different saddles, different saddle setback, and slight saddle tilt. None completely fixed the issue.
When out on the road I move around a lot on the bike, thus spreading saddle pressure out to different areas. On the turbo though I do much less moving. I forced myself to stand up regularly during yesterday's turbo session, which no doubt helped me get through the hour, but I came to the conclusion that I need a much more upright position...
I had a straight handlebar on the bike and the stem was as high as it could go so I ordered a stem riser to use to get the bar higher. That is due to arrive tomorrow. I just remembered that I had a spare drop handlebar in my junk box though and had the bright idea of fitting that and turning it upside down, like we did as teenagers. (You did that too, right?

). It gives an option of a very upright position. I can still grip the tops to get a lower position if/when I want to but I can hold the inverted drops and sit up the rest of the time. It looks stupid, but who cares!
A very quick test suggested that this might work. I will do another turbo test session tomorrow and see how I get on.