Ah yes you're right about that there is some junk in it. I can save upto 25MBs of space if I remove the pictures and videos that came with but yes, SenseMe and other features aren't that appealing.
Sony should atleast give external card support to the Walkman. They simply cannot put up with competition with their Cowon and Sansa counterparts.
Speaking of displaying filenames, you cannot do that while in playback screen but if you go through Menu --> Music --> Folder --> (Your music folders/files here), this way they do show up with filenames instead of tags. It might help you.
And Kudos to you for getting the 16GB E475, I can only dream of the extra 8GB space now :P