Its a slightly different type, of course, but joy nonetheless (perhaps excitement vs contentment). In other words, its like there's a natural "limit" on the happiness I can enjoy at any given moment, and going to great lengths to "live the dream" might be pointless, except to look back and enjoy that one did it... a happiness investment perhaps?
Its been hugely freeing as I had been having some thirty-something angst about prior life choices (as you do).
Has anyone else experienced this? Perhaps if a far more common idea that I realise and there's proper terminology for it.