Voiceover or not?

I'll jump in here with some useless info. The company I work for put in a policy that we will have professional voice over. We found a good person to give use files to put in our projects. And yes, they are expensive. I think we paid for a new car for him last year. He sounds great but we are locked into one voice. When we do translations into other languages (non-English) we use a computer-generated voice. 

I like natural real voices, but they cost. If you need to make changes, these can add to the cost. If you voice person is internal, they may leave. Now you may need to revoice a whole project. Computer generated voices are not that bad anymore. I find many of the Articulate voices easy to use and can be adjusted when needed. I would like to see some improvements, but I'll wait. 

As for the learning. I don't like someone just talking to me. I like spoken instructions that I can follow. A slide with a lot of clutter that is being read can be boring. Look at presentation on YouTube or other channels that you are learning from. See what you like and what you learn from. There are so many different generations learning on-line today with many different preferences. 

Choose what works for you and present that to the stakeholders.

Good luck.