Well, I note that everything at the top of the hill, and likely behind it as well, is brighter, with cheerier colors. I see this climb as a transition. Is he climbing towards that woman in the distance? I feel like this is the end of his trials of a particular nature. I think that this won't literally be his last hill to climb, but the last challenge before some form of rebirth.
Basically, he is emerging from shadow into light, which could be akin to many different interpretations. He still has to climb the hill of course! But we can see that he is a seasoned traveller and has much to look forward to. The girl waiting for him promises comfort for sure. The details are up to the viewer to embellish. Thank you kindly for your thoughtful and insightful comments - you pretty much saw it how I hoped!