if some improvements such as mines gave fractional negative health (which could perhaps be scaled higher on monarchy/imm/deity) this could b good. I really think the governor pets and menagerie are easy candidates to remove the +1 happy. Also the dog trainer having +1 happy +1 health seems excessive. I feel that resources shouldn't be changed as they are a good tool for game play and strategy.
Someone should go through all the buildings and slash all the +gold and +happy and to a lesser extent health.
As far as health is concerned having negative health in a city isn't actually a big deal since with +9food farms a few unhealthy citizens is really no biggie. So on second thought maybe slash +health too
Come to think of it, a good idea would be that excessive health problems or excessive happiness problems have a mutually negative effect on each other. If your people are unhappy (above certain amount, maybe -5 for example, this would cause -2 health and vice versa. This seems intuitive too since its realistic.)
*while your at it increase all the wonder costs too