Upgrade the slides editing interface to make it more like PowerPoint or Google Slides. Add a bit of complexity to it. It's very annoying to use at first, especially when people have most likely used PowerPoint or Google Slides before using Presenter.
PLEASE include a much more sensitive color picker. Especially, allow users to select and use a personal collection of preferred colors.
I'd possibly not focus on adding more functionality here as most people have access to Google Slides/ Keynote/Canva/PPT ??
I'm more likely to use inbuilt slides for liturgy (for example) which is better using the Song/Lyrics features- multi page, consistent templated fonts ....
A good starting point for improvements would be to allow user defined fonts (with size, colour, shadow et.) rather than imposing 22 point Tahoma every time you start a new text box.
