Back in the day I went to broadcasting school. That's why, I mentioned it. I hope you don't mind. Here are a few tips. They might sound silly but they really do work.
1) Smile when you do your recording.
2) Give a rhythm to your voice / script without becoming sing songy.
3) Punch keywords. Example, sound excited, joyful, energized but without going overboard. The tone of your voice remains smooth and consistent but you punch keywords or phrases.
You're right, slow down just a touch. Otherwise, I thought you sounded pretty good.