If there are a lot of fields and different subtables it makes sense to group different fields to a tab or to a accordion to provide a better overview about the page.
Edit can be done in the actual forms configurator by using groups and group elements.
It's an interesting proposal.
Tabs would probably require lot of work, don't know if it worths; accordions are probably easy to implement if we use the (already existing) separators but I am not sure if they actually improve the usability of long forms.
CSS and js is implemented within DaDaBIK.
The view (html code) can be generated by the user by using low-code. The html code can be implemented at a special field in the forms configurator or at special include files like php pages or html pages. The fields are added in the html code with dadabik_field fieldname dadabik_field and will be replaced during generating the form.