Layouts
Avada demos and Enfold demos are predefined layouts that can be used as starters to build a website. The Avada themes are more diverse than the Enfold themes. Consequently, when you want to start a new website there are more choices with Avada.
Theme options panel
The theme options panel from Avada is much more advanced than the Enfold theme. The Avada option panel is so advanced so that in order to build a website you don’t need to modify the CSS styles. On the other
Page builder
The page builders from Enfold and Avada aren’t very different from each other. Both of them allow the web developer to modify the post and pages in the back end. They features many elements like accordion, countdown, progress bar, icon, icon box…


License & plugins
It looks like Avada requires a license for every new installation. It requires a key to be able to download the necessary plugins that help to modify the theme. On the other hand, enfold has no plugins. All the functionalities are embedded in the theme. Consequently, if someone wants to build an Enfold theme and the CSS is ready, it is very fast to build the website since it requires the installation of theme and the CSS.
Performance
Enfold is the champion of wordpress theme. It has a 100/100 GT metrix score. Avada is slower than Enfold in back end and in the front end.
Spammy structured data

On the other hand, the Avada theme has only one microdata markup to mention the breadcrumb (homepage>your category>your page). With only one microdata markup I think that it is not likely to create a Google penalty.

To stay away from penalties related to structured data I strongly encourage you to ensure that
<script type="application/ld+json">
{
"@context": "https://schema.org",
"@type": "Organization",
"url": "http://www.example.com",
"name": "Unlimited Ball Bearings Corp.",
"contactPoint": {
"@type": "ContactPoint",
"telephone": "+1-401-555-1212",
"contactType": "Customer service"
}
}
</script>