Might want a /usr/local/sbin directory as well, depending on if any true 'system' tools might ever need to be installed.
Also might
not want to change the file extension from ipk (it's ipk, not ipkg - by the way), and instead use a formatting like package-name_version_iliad.ipk (such as foo-bar_1.0.4-5_iliad.ipk). We really don't need more file extensions floating around, particularly not five-character ones, in my opinion... I mean, renaming ipk into iliad, which was originally based on deb, which was packed as an .ar or .tgz archive... It gets confusing. Maybe even just use 'pure' .deb files, as Debian has some excellent tools for managing those already. Of course, I'm not an iLiad user...
(Obviously these are just ideas/suggestions, ignore them if they're not helpful.
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