Decidedly less happy, I think. For one thing, it would be virtually impossible for me to find Ms. Right without the money thing creating an adverse selection problem. I'd also virtually have to have People, because you simply can't be a billionaire without having People, and I prefer to spend my time with people rather than People if you catch my drift. I don't want to ever have my own accounting office.
I've been doing sit-down-think-this-year-through budgeting for the first time in several years (because a salaryman has virtually no need of budgeting: you're paid exactly enough to live the salaryman lifestyle and since you don't have time to do anything else what the heck would you need money for). There is a gap between my new means and my desire (e.g. I'd like to be able to travel abroad three or four times this year and my current income will not support it), but it isn't a ginormous gap and I expect to close it fairly quickly. So there's a marginal happiness return on income for me up to, oh, call it $80k a year. Throw in a nice young lady and a bit of support for my family and I might even have a marginal happiness return up to $200k a year. After that, it might as well be WoW gold for me: having the number increase over last year makes me happy because it means I'm doing well at the game, but it won't have a significant impact on my life.