There is a reason why many presentation templates and data dashboards look so bad: they have been designed without actual data.
Most corporate presentation templates are the result of the work of a designer who has been given a white page to add some stuff to. The resulting white template page might still look OK, but when it is filled up with typical slide content…
Information dashboards looked great in the mock up screens: dials, tables, buttons, graphs, until they are populated with typical data: text blocks are longer shorter than in the mockup, important data is actually not there, non-important data is, all graphs look flat, and all dials have more or less the same color because the values don’t change that much.
Presentation template designers, ask for an actual deck to start working on. Dashboard UI designers, ask for a real data set.