Salt.
Restaurants like salt because customers won't order water (even though tap water is free here in NL it makes one look as too much of a cheapskate); they'll order a drink like wine which they can upsell and already has large profit margins.
Nephrologists won't be happy though (although it does generate them more customers, they probably got more than enough as it is).
My suggestion would be: less salt + umami + herbs.
Herbs is a bit vague, it really depends on the dish (and there's more than herbs; look at things like garlic, ginger, and turmeric you can buy these dried as well, in same tins or glasses as herbs are).
Personally, I'm a fan of the Italian spices as well as mixes like baharat and ras el hanout even though I don't have a background in any related culture (I'm Dutch).
You can achieve umami in various ways: yeast extract, Vetsin, E621, MSG, etc. In the end its all the same, but I put the one consumers fear the least first in the list wink
https://olumialife.com/knowledge/how-does-insulin-affect-lep...
For cooking, I understand olive oil is unhealthy (I think you create carcinogens as a side-effect), as are many other oils, but that coconut oil doesn't do this because of its different melting temperature.
I believe the situation with oil is a bit more complicated than that, and you're generally fine with olive oil unless you make it smoke, which is fairly non-trivial to do, despite its low smoking point. There seems to be some debate on the topic: http://www.seriouseats.com/2015/03/cooking-with-olive-oil-fa...
Coconut oil in particular actually has a low smoking point. If you want to be safe, you want Avocado oil.
I initially felt the same way as you wrt tastiness, but had a friend bring me back a tin of oil from Italy recently and whoooo boy it's just the most phenomenal thing. Add a bit of salt & pepper to a shallow bowl of oil for dipping bread.
Olive oil with herbs is amazing. Give it a whirl.
Reposting the question from the comment:
> Doesn't fat make food more satisfying, making you feel fulfilled sooner?
Needs a citation I guess.
For most people high fiber foods are better.