I DO NOT want to BUILD playlists. Either cut and paste, or like Songbird, import media and be done with it. Rhythm will play single songs off the HDD, but trying to import a file or cut and paste, you can forget about it.
In Musicmatch it is File, Open, double click and it plays the entire file, regardless of how many files are in the file. In this case about 1600 songs.
Please explain yourself, "regardless of how many files are in the file
" or "to import a file or cut and paste" makes little sense to me. Are you referring to .m3u playlists? Or just "play everything in <that> directory" feature? I can't think of anything else. Copy&paste feature (ie. select files in a system file browser, control-c, select player window, control-v) might be useful, but I imagine it would need a lot of clipboard<->player interaction, not to mention dozens of file managers. Besides, that's called "building a playlist", ie. something you don't want.
If you are referring to auto-building a music library from a directory structure based on id3 tags, ... then I'm probably not the right person for the job.