This might come off the wrong way, but if that was all truly out of your own head on-the-fly speech, not prepared in conjunction with or corrected by anyone, then you are either the most dedicated or the most talented Japanese learner I have ever come across. Your intonation and (lack of) accent are simply outstanding, and since that is something nobody can possibly do for you, I must say my conclusion is that your hard work and/or gift for picking up a language are to be admired.