Great article.
Nice details. One thing I see that you may want to think about changing slightly is the angle of the ladder. Making it a little less steep might help.
Thanks for the thoughts and rec. I think because of the slope of the hill, the ramp angle looks a little more exaggerated than it is in reality but I'll definitely keep an eye on it, particularly as they get more heavy footed. Thus far they've been doing fine with it.