I'm curious about what tasks you're looking to accomplish. While there are no direct analogs to the features you've described in C1 and LR, there are ways to see all the keywords/metadata for a selected set of photos -- The text exporter can quickly generate a text file (or even a spreadsheet) that shows whatever metadata you choose from a specific selection of photos. I am not sure if any of this could be used as a workaround for what you are looking for -- I guess it depends on what you mean by "proper overview." For many tasks, of course, a spreadsheet might not be at all helpful -- but if you have a specific goal in mind, there might be alternate ways to do it.