There really is no easy answer to your question......too many variables. For example, last summer, I landed a strip in my PA 11 on 26 inch Airstreaks. A friend landed his PA 18 on 8.50s and cursed me for telling him the strip was fine. He thought that strip was too rough for him. In that case, the variables: Different tires, different airplane weights, and most important, different pilots and therefore perspectives on what is “too rough”.
And there are several other variables: touchdown speed (STOL kits, etc), landing gear configuration, and so forth.
The best procedure is to learn to lightly “tickle” a surface with your tires on one pass, then put a little more weight down next pass, and continue that process till you’re comfortable landing there, or decide to go elsewhere. Of course, there are one way strips where this doesn’t work.
But the process noted is the way i pioneer a landing zone (as opposed to an “air strip”).
But, again, what I might be comfortable landing in a particular spot, you might not be happy with at all.....and vice versa.
This is one of the fundamental skill sets that you have to develop to operate off Airport or on many back country strips.
MTV