for 1, there is a preference setting in the Player options to remember the last playback position on startup. Also anything in the AudioBooks section automatically remembers the playback position
for 2, thanks for the suggestion
for 3, i'm not sure exactly what you want so could you add some more description. Just FYI, on the computer tab the drop-down allows you to show files from sub-folders so with all the files displayed you could use the normal search functions