Hi,
thanks for your question, and sorry for the trouble.
The rows are this high because the data of the table obviously has to go somewhere… If you don’t want the cell height to increase, you would have to increase the widths, but then the table would overlap the sidebar, which is also not nice.
Your table simply contains too much data for this limited space.
One idea could be to add horizontal scrolling, e.g. with the scroll
mode of the TablePress Extension from https://tablepress.org/extensions/responsive-tables/
Showing tables in a popup or overlay is certainly possible. However, TablePress does not have a feature for that built-in. You would have to use a lightbox/Thickbox/overlay plugin for that.
Regards,
Tobias