I'd Like to Travel

My fiance and I are planning for a vacation this December. We're into outdoor activities like hiking, experiencing the local cuisine etc. I loathe shopping complexes. Those monolithic, concrete superstructures that induces a massive eyesore. Those are dime a dozen in KL. Honestly I cannot comprehend the allure of big, monotonous metropolis. Traffic jams, boring supermalls, congested public transport doesn't excite me. So we're looking at places like Cambodia, Vietnam or Philippines. Any ideas for a cost effective yet fulfilling eco tourism?