Hi Mark,
I know that in the Site Library (with GP Premium) one of the “page builder” options is “None.” I assume this means Gutenberg, but can I use the classic editor with the starter sites? or would I loose a lot of functionality?
Yes you still can use the classic editor and yes you will loose significant functionality especially for themes that uses GenerateBlocks as you won’t be able to edit them properly as they where made with Gutenberg Editor in mind.
I did a search for “starter sites classic editor” but got no hits.
Yes you won’t find one specific to this. And we really can’t recommend classic editor knowing it’s about to be obsolete as Classic Editor plugin will lose its support in December 2021.
Leo had told me that Elementor might slow the site down and for speed it would be best just to use “none.” Would this still hold with the Classic Editor plugin as well?
No its not the same with Classic Editor, but you will lose a significant amount of functions for editing things.