This is basically saying don't marry unbelievers or appropriate within their worship culture, you are not really even supposed to swear/pact (Mat 5:34), as it can lead to hurt feelings if you fail to do so. You can treat them as you would anyone else, if they ask will you help me? Say yes or no.
You have a good point, but a dispute to this is that the man should lead his family if present, if he won't step up, the wife has to do it. If he is not present, the wife is bound to fill his role, and vice-versa. Furthermore, marriage is completely optional, and is not something everyone does. Also, submitting to a husband is not being his slave, because if it is, the husband is a failure at his role for not taking care of his wife's needs, so a properly cared for wife would never be unhappy or want a change.
The question is, do we have to follow everything correctly to get to Heaven? As long as you are helping people out, I don't see how having a little extra money is going to hurt if you devote something to the poor. If everything had to be done perfectly, we would all be going to the underworld. 1st Corinthians 6 gives us a very good example of sins that failure to fight are going to send us to Hell, having a little money is not one of them. Also note, failure to submit to a husband isn't one, either. This is the basis of my list to OP.