You cannot increase ramp test intensity. You could manually change your FTP, which will affect the power at each ramp, but you can’t do at say 101%. It’s a fixed increase at each stage.
Bailing on the ramp test is not ideal if you did it simply to not go all the way. It’s a capacitive effort, which means in context that last minute should be your limit. I appreciate what you’re saying, but I’ve done 20 minute tests and the ramp test after extended breaks and it has not negatively affected me in the ways you’re describing. As stated above, it’s very common for people to tack on an easy z1-2 workout after to spin out their legs, and the test itself is designed so that you can start training the very next day at a meaningful level.
I think you’ve got a psychological preconception about how it’s going to feel after completing it (or perhaps how you felt one time) that’s not strictly accurate. 20 minutes of building up to 1 minute of torture is not as bad as all that in terms of physiological demand and required recovery.