So what does the Happiness stat for colonies actually do? (Does it slow down/speed up the rate at which they pay rent or something?)

The security camera network you can build that generates research; does this increase your passive research gain while your running around, or is it generating an item that you have to go and physically pick up like the old computers before the tree existed?

Do multiples of the same object stack for happiness bonuses, like 2 Recycling bins? Similarly would two security camera networks stack and generate even more research?

I know I can test these things myself for the most part, but I am having issues with the amount of research generation I have and am just trying to spend my points wisely, hoping someone who has already invested in these things could share their findings.