Personally I feel 180mm is to long for 617, I use a 75mm with mine and to me that's a normal lens. I usually also have a TLR with me with an 80mm lens so in most ways the lenses have similar perspective the essential difference is that in the horizontal plane I have much wider capture, but it's essentially very similar in the vertical plane.

However I'm not shooting in wide open landscapes like you have in the US so a longer lens may suit your needs, I actually found a 90mm a louch long in the landscapes I work in in Greece & Turkey.

You can get a Chinese focusing helical quite cheaply or do a search and see how Steve Smith made one from an old lens, that would be a better option than relying on hyper-focal distance with a 180mm lens. Most point and shoot cameras use wide angle lenses.

Ian