Enable more style options in the theme editor such as font size and font weight. On your page, https://www.metaslider.com/documentation/styling/, you state:
If you’re not comfortable with editing the CSS yourself, you’ll be glad to know that Meta Slider Pro includes a live theme editor that lets you completely customise the style of your slideshow – no coding experience needed!
I really do not think it is accurate to say “lets you completely customize the style” when you cannot do these two simple options. I can certainly edit the CSS and feel comfortable doing so, but I expected more in purchasing the pro license. I prefer not to hack up a WP instance in the editor and seek plugins that support it properly.