About #3, do you view this as a hard rule? Not the animal part (vegan btw), the "hurting is always wrong" part. There are situation where I've caused harm to someone for the sake of others, their future, or a greater pleasure.
Also interested in the "not killing you own species" section of #4. I would also kill another animal rather than a human, but for other reasons. What do you think about hurting a member of your own species is uniquely bad?
The hard solipsist would disagree with you already from the 4th word. Your assuming an other to try to convince someone of their existence.
Here are a few theoretical realities:
The perceived existence of language is compatible with all of these, is it not?