Datagrid 2 is great for searching for data but a really useful option from the previous datagrid was the ability to export to excel / csv.
I understand this is a bit difficult due to the custom content property / dynamic content for a cell but you set the attribute for the column which could then be used.
Maybe restrict it to XPath again and and add a popup to add the appropriate query to add in an expression editor (ie the filters since you can wrap the table in an entity to hold the filter values to then be used)? Similar to microflow list operation Filter by expression.