A lot of my perspective of a place comes from the people - let me give you an example of Stockholm. We really were only in the Stockholm area and the archepeligo there, so perhaps the key is to go outside of that particular part of the country. They might be happy as a country, but the Stockholm people are miserable toward others.
Me, walking into a quaint shop in the Gamla Stan: "good morning - wow, you have some beautiful things."
Employee, eyes down: " " (as in nothing - no hello, no thank you after purchasing, no interaction)
Getting on trains or buses people run into you and don't acknowledge it, I watched a pregnant lady with a stroller get on a train and nobody moved to give her a seat. Zero eye contact.
In fact if you google rude Stockholm rude you'll get a ton of hits. Some say it's because they spend so much time alone in the winter and the dark and then when it's light and they go outside the stimulus is too much. Some say it's anti American (that we're too loud and involved with strangers), some blame racism. But let me tell you it's real. I've got a very full passport and been to multiple continents and I've never felt like I was less wanted to be visiting somewhere.
Edit: as far as happiness goes, guess just because you're personally happy doesn't mean that you're nice.