There is one thing you can do right now that will boost your slides: reduce the number of words per slide. It is that simple. By reducing the number of words you make your audience happier because first, you'll naturally increase the font size of the text, and second you will stop reading your slides even start looking at your audience.
The fastest way to reduce the number of words in a slide is by splitting its content into several slides. There is no country in the world with a slide tax, so don't worry if you end up with 3 or 4 times more slides. This might even be good, for it might help scoop the unnecessary detail.
Light Bulb designed by Shane David Kenna from The Noun Project