I would consider the entire ride ...or at least to the 32.5 mile mark. I calculate approx. 3K feet of climbing for the first 32.5 miles of the ride.

I think that's a moderate amount of climbing for that distance and elevation. If you were to sustain that profile for a century ride, then I would say it's a moderately difficult ride.

But that's not a very inclusive analysis. There are so many things that could make that ride very, very difficult. When you start adding things like cadence, wind, gearing, load, experience, health, age, (and so on) into the equation, you could come up with an entirely different profile of degree of difficulty.