Starting from NextReports 8.1 iframes will be able to contain in their url some new parameters alongside width, height and report parameters. See this old post about iframe parameters.
Two of them are meaningful for table widgets: tableFontSize and tableCellPadding in points. These can be handy if you want to have an iframe on a big monitor screen and users need to look at it from distance. To show the difference you can compare following two screens:
Another parameter, adjustableTextFontSize, has a boolean value and by setting it to true the chart from iframe will have texts from title, legends and axis values adjusted in concordance with iframe width. This parameter is automatically set to true on chart Detach action from NextReports Server.
A simple comparison can be seen here: