Lot of interesting ideas here. I would just add a few points. On listening to your gut when you are a brain person, this is actually trainable, check out the b

Lot of interesting ideas here. I would just add a few points. On listening to your gut when you are a brain person, this is actually trainable, check out the book Focusing by the University of Chicago psychologist and philosopher Eugene Gendlin. On deciding, it seems to me the two most important things are if the two of you have reasonably common values about how you want to live your lives, and if you trust the other person's moral character and ability to act rationally, at least when it comes to something really important. If the two of you have these, then you can probably work out the difficulties. Thirdly, you stand a much better chance of settling problems small and large if you take a course in interpersonal relationship and conflict resolution skills. See for instance Nonviolent Communication by Marshall Rosenberg. Lastly, you need to have some larger philosophy or religion to keep things in perspective and as basis for personal value beyond how much your mate loves you, otherwise you will either be their puppet or try to be their master.