Nice list. Note that I would prioritize grammar over vocabulary until you're able to form correct sentences in real time conversation. But first, make sure your pronunciation is accurate (not necessarily perfect, just accurate). And of course, attitude is key to everything in life.

Phil gave an excellent answer.

Once you are able to have a conversation, confidence is the most important! :)

When you are swimming -- moving a left hand, a right hand, a left leg or a right leg, which is more important? 反诘