Oh!! I came back to what I thought was a dead thread only to find I had actually received some super helpful advice! I apologize for that, after my last post in this thread I really didn't realize anyone else had made any replies. I actually just came back here to revive it one last time to post my finished work, only to find if I had seen your tips I probably would have a better looking finished piece here..
Decroded, your recommendation for the mountains and river highlights were lovely! Because I was combining an imagined foreground with a photo referenced background, I wasn't sure how to go about blending the lighting to make it consistent and believable throughout. Instead of adding more highlights to the mountain range and river I instead lowered the contrast and tried to add more of a slight Swiss Alps haze to the whole scene. It made it a bit easier for me to finish everything this way, but if I had seen these replies sooner I would have probably gone with Decroded's method of highlighting the background. Oh well, there's always another landscape to pixel next. :] Thank you everyone for the great advice and suggestions, I learned a lot with this piece!