javascript front ends like angular and react offer great solutions for routes and sub-routes to easily create menus and sub-menus that load content without page reloads.
There are a lot of great existing drupal layout tools that allow custom layouts to be rendered server side. There appears to be a trend toward throwing away all that great work in favour of pulling json from the server and rendering on the client.
Is there a means to pull pre-rendered html (via AJAX) from the server and put it wherever I want on a page. if drupal had its own ajax router system (with sub-routes) js clients could pull pre-rendered html from the server saving low power devices from the task. this would be a great alternative to front end json based routing...
perhaps i am missing something from existing drupal features. is there an easy way do this already?