Unlike the others on this thread, I do use folders. I choose in the Import dialog to organize by date, with a date folder within a year folder - and then right after import I right-click on the date folder and add a description. My thinking is "Why not?" It means I can decipher what's on my hard drive, and I can access a shoot very quickly in LR without having to set anything else up. I agree that subfolders by file type are not necessary, but if they work for you, then again, why not - they essentially act for you like a saved filter. I can see that it would be more useful to have your file type subfolders within event. I'm having trouble understanding this though: "However, this would mean I only add the Raw directory to Lightroom. The catalogue entry of that dir then reads "Raw" of all my photos. So there's a need to rename the parent directory in LR, but not on the hard drive." I also get rid of exported JPEGs since I can recreate them as needed. But given that you like to keep yours, have you thought of managing all your file types in Lightroom (including videos)? If you did this, then you could use the Folders panel to rearrange your folders to achieve file type subfolders within events.
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