The research I linked claims to be evidence for 2 and 3. I'd say it's not irrefutable evidence but it's more than 'very little'. Do you take issue with specific aspects of the research?

There seems to be a certain amount of politics tied up in happiness research. Some people prefer to believe that improved material wealth has no correlation with happiness because it fits better with their political views, others prefer to believe that improved material wealth correlates strongly with happiness. I find the evidence that there is a correlation persuasive, but I am aware that I may be biased to view the evidence favourably because it is more convenient if it is true in the context of my world view.