re: Question: What makes things want to reproduce?
"What seems to set evolution off is reproduction: For the first "thingy" ever alive, how does staying alive longer lead to reproduction?"
It seems to me that life is reproduction [creating/transforming stuff]. Cells [Life] makes cells, some cells are made to specially for transport to other areas [sex cells].
So, life is about making and moving. Staying alive allows more [or any] making and moving.
For intelligent creatures we sure aren't moving off the planet very fast.