I only have a single set of 400 gram boots that I hunt in almost all year. When it gets super cold I use a set of boot covers with disposable hand warmers in them.
If Im in the hills where walking in mud and water is not an issue, (and trekking long distance, shed hunting/scouting)....I just wear a high end pair of Asics or Solomon's. I can easily do a 10-12 mile hike with no discomfort. For short distance walks while hunting, 2-3 miles, I wear Irish Setter VaprTrek for early seasons and Muck Wetlands late season.