LEC- I totally agree about the out and backs! My husband thinks I'm crazy because I also planned my running routes specifically so I wouldn't have to just stop and turn around randomly.
What keeps me going in new scenery. Walking/running/ hiking in the same areas gets boring to me pretty quickly. As far as training goes, you could do multiple loops of the shorter trails you're doing. You could also pack a bunch of items into a backpack to carry with you. I've actually run into a few people doing this near my house (middle of suburbia, not mountains
)practicing for backpacking trips. I'm glad you found an exercise you like! I love hiking and would go more often if I were closer to places I could hike!