Oxwall already has this.
If you don't see auto updates requests, read this http://docs.oxwall.org/...st-in-my-admin-panel
As Tammy said, ftp questions has been answered many times. Usually they are caused by incorrect ftp server setup, when ftp default user's path is not set properly: Oxwall is unable to detect your actually software's location in this way. Search the forum please.
Auto updates work in the same way as you know it on WordPress:
- you should put ftp details once for updating all plugins and themes within the one session
You say you and your hosting providers have tried logging into FTP to add/update plugins/themes. That isn't a problem on Oxwall, but your specific site. Now, I know that's not your reasoning but you're using that as your base to say that Oxwall should do updates "without FTP" like WordPress. If I recall correctly, WordPress still requires FTP details (though they usually get them by default). They just over skip the step - not only that but on Oxwall entering your attributes for FTP once will usually make them last anywhere between 5~10 hours.
I also believe making an auto-update feature with no FTP check/login would be bad. I don't think it could stop for only commercial items - it would have to function for both free/commercial so people with slight to expert knowledge could use that for exploiting people.