"Who is rich? Those who are happy with their portion.”
- Ben Zoma
One of the ten commandments says something about not coveting, there is a reason for this commandment, more than just stopping sin, it encourages happiness.
Contentment" seems realistically defined as "enjoyment of whatever may be desired". That definition is realistic because the more contented an individual or community becomes the less extreme so more acceptable their desires will be. Contentment is an intuitive so natural concept whereas "peace" is a civil and so non-intuitive concept dependent on restriction - for that reason endeavors did and always will lead to war - whereas contentment was and is self sustaining if civil / religions affects are displaced.