You have (in my opinion) a good solid start with some of those voices. Some things I would probably work on is some mic technique. Such as when you know you are going to get louder, back away from the mic so that it doesn't distort your voice. Another thing is on your "plosives" your P's and B's and such you will either need to turn your head slightly so as to make the sound no travel directly to the mic or get yourself some sort of pop filter to nullify the pops it creates. All in all, this is a good starter and I for one am looking forward to seeing you improve as time goes on. Keep it up!