Besides Markdown syntaxes VuePress itself adds,
vuepress-theme-hope enables more syntax in Markdown via vuepress-plugin-md-enhance plugin.
VuePress comes with GitHub-style tables, Emoji, TOC, code line numbers, specific line highlighting, etc. are all available out of the box.
For detailed syntax, please see Built-in Markdown Enhance.
Enable Markdown Enhancement
plugin.mdEnhance in theme options will be passed to the plugin as a plugin option. Visit plugin documentation to see the usage.
Don't worry about the size of your site. If you don't enable related features, the final code won't include code for these features.