I think 99% of people are horrible at taking vacations if their goal is happiness. They stress themselves out way too much and also fail to push themselves personally. eg. running around to see a bunch of tourist attractions is both stressful and not rewarding in any way. Also, sitting on a beach somewhere nice might feel relaxing at the time, but provides no long term happiness at all (though that's one case where the anticipation of it might really be the happiness - eg. people who live in the cold and take an annual winter beach holiday, the actual vacation does nothing for you really, but all those months in the cold you can look forward to it).
Anyway, if you just want a good normal vacation, you should both stress less and do more. If you're not retarded, that's quite easy, you just don't worry too much about planning, give yourself plenty of time so you're not in a rush, but when you get there actually do the interesting activities, don't just sit around and be lazy or be a pussy and be too afraid to try anything risky.
The longest term reward you can get from vacation is to push yourself personally in some way, eg. to learn something, or do something that's outside of your normal character, have experiences that change you significantly in a way that will stick with you for a long time. eg. take a vacation boating some islands and live aboard a ship with a teacher and learn to sail, or stay on a commune and farm and force yourself to be non-judgemental of the dirty hippies, or take a vacation where you are an S&M "gimp" in Berlin to expand your kink horizons, etc.
Anyhoo, I think the next trend in boutique vacations is "identity vacations" where you pay some package to travel somewhere and be some new character. They give you the right clothes, the right place to stay, and some accessories and a guide to integrate you into that lifestyle. So you might take a "I'm gay in San Francisco" vacation or "I sell jerk chicken and make dancehall music in Jamaica" or "I run a bar on the beach in Mexico" or "I'm a fixster in Brooklyn" or whatever.