"1) The productivity of the startup is mainly the sum of the traits of each individual. Plus, to a lesser extent, the synergies between them."
I would argue the synergies between cofounders to be the single most valuable entity in a partnership. You may have complementary skills but if you don't come together and are able to do incredible things that are spurred on by eachother. Spark is key - this linear trait argument isn't correct at all. Never compromise without spark.
You don't know by chatting with someone - best to work on something non trivial together and figure out if you get on.
This seems like it could be an interesting feature idea -- maybe I could include a way for people to solve a problem together after they introduce themselves?
I would argue the synergies between cofounders to be the single most valuable entity in a partnership. You may have complementary skills but if you don't come together and are able to do incredible things that are spurred on by eachother. Spark is key - this linear trait argument isn't correct at all. Never compromise without spark.
You don't know by chatting with someone - best to work on something non trivial together and figure out if you get on.