Quota across sites works ok but please add trial support, it's important.
Also, auto-deluser needs to be an option for the failed, nobody is gonna pay attention to doing that manual. It's very easy to implement, just needs to send one cmd to all ftp's: site deluser <user> or on gl, site change <user> flags +6 also works. If host box is gl, crontab could trigger the checking if users passed at end of week/month. If host box is io, you'll hafta think of a way, maybe scheduler can do it.