Just throwing out a couple ideas. Some of these may already be in place, just not documented.
*Create a wiki-tag to embed uploaded attachment images/files.
image:myimg.jpg or image:Main/myimg.jpg instead of http://localhost:8080/wiki/Main/file:myimg.jpg (intent is to show image inline)
file:Main/samplesrc.java instead of manually creating a link to http://localhost:8080/wiki/Main/file:samplesrc.java (useful for future clustering attempts as well). Could also be useful if you use the image: tag for thumbnails and file: tag for downloading the actual image file (i.e. file: never embeds the image).
*Configuration option to allow or disallow embedding external images (i.e. if using the image: tag, only uploaded attachments and not external images). Policy or bandwidth reasons to not use external images for embedding into the page.
*Allow renaming of files on upload.
*Retain and come up with display options for the upload date and the 'uploader' for all attachments.