I think its a bit sad that its only when we start getting older and have had time for introspection and reflection that we realise that the only thing we have of value is time.
We are dying from the time we are born and our bodies are changing everyday. They will not be the same, its when you get sick and realise just how valuable even feeling normal and healthy is that your appreciate the sense of normalcy. If it affects your mobility, sense of well being, physical state, your quality of life and quality of of your time drops never mind your wealth. A lot of people don't have that luxury of recuperating or feeling normal. I think its not money but our health that can make us really unhappy.
We have on average a 'journey' of 60 years in this beautiful planet to make the most of the time we have, to make it meaningful and I think what ultimately makes it meaningful is filling it with experiences, learning and people.
What you have done with the time and not necessarily money could be a good indicator of overall well being. Though money can more easily enable access to new experiences every experience is different and has merit irrespective of wealth. Learning new things, new sports, new skills are more valuable than anything else as that time has been used and you will not get it back, but you have something to show for it that anyone else can only get not with money, but spending the time to do it. For instance losing weight or learning a new skill. 10 months down the line you have achieved that and are much happier for it and no amount of wealth can buy this for you or anyone else.
I am generalizing and they are exceptions but when you think about it our deepest and happiest moments are social, about other people; our family, friends and interactions with other people. This has the potential to make us very happy and fulfilled or very unhappy irrespective of wealth and it's experiences with loved ones; parents, siblings. family, kids, relationships that make up our happiest moments.
Everything we associate with happiness in terms of money it seems is often only meaningful or valuable in a social context, and it is always related to it in some way. With the exception of some personal goals that give a sense of achievement in itself, a large proportion of achieving our goals in isolation is meaningless, its only when its widely acknowledged that it becomes meaningful and valuable.
This is not to say money is unimportant as it can be a source of stress and limit our ability to have experiences, It's an economic system that drives our progress and is intimately connected with all aspects of our life. But a wealthy individual has experiences as does a not so wealthy individual. I don't think you can objectively say the wealthy person is happier, I think its the person who has had diverse experiences with his or her time and a fulling social context that perhaps is 'happier' as these are unique experiences that give happiness.
We have to except the desperately poor from this as access to basics like healthcare, food, sanitation, education can completely change one's perspective of life and make the time we have meaningless which is why social security and basic income is essential to dignify human existence.