automatically number the lines

Joomla lacks the feature of nested fields in subforms. This makes it difficult to create a subform with a large number of fields. Admin layout in table or default form, because of a large number of fields, presents the subform layout in an inconvenient way to work.
In table form there is a large space between the fields.
When there are a large number of fields, scroll to the side. very inconvenient
In my opinion, the rows should also be numbered automatically so that row numbers can be referenced when retrieving the data. Admittedly, you can add a row number field and write down the row number, but this is very inconvenient and also takes up space since the size of each field is the same regardless of the length of the content. Too bad it can't be changed accordingly.
I work with the Yootheme pro builder and theme which allow more convenient editing but I would expect some solution since my preference is to work with dynamic content.
Is it possible to create a different layout on the back of the site, to automatically number the lines?
Regarding nested fields in subforms, I understand that this is a Joomla problem.

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