If parity with Curse is being considered, you may want to take into account the new CurseForge stack. It's currently in use by WildStar, and WoW will be migrated to it at some point before the heat death of the Universe.
The main thing is that at least for WildStar, they use pkgmeta.yaml instead of .pkgmeta. This isn't likely to be a huge deal since they appear to use the same key structure, but it's something to keep in mind.
http://wildstar.curseforge.com/docs/packaging
The new stack also uses GitHub webhooks, which from what I understand would then trigger the packager to generate a zip based on that commit/tag.