But, if this isn't a framework then it seems rather large. If it were to do only what you describe, simple classes for simple changes, then you are loading in lots of stuff in your inc imports that isn't required.

I don't necessarily have a problem with it, it's not a bad idea. Personally I wouldn't be against using something like this that's tailored to a design so that only the necessary classes are required. That way it isn't necessary to have stepping of 1 to 100 on each property.