Own domain/non iCloud email with iCloud

I would like to be able to use iCloud with my own domain email, so as to keep my iCloud ID private.

I have my own domain (hosted by pobox.com) that forwards mail to my iCloud account.

So far I have these work arounds:

On Mail.app in OSX Mavericks, I simply change the From field with a "Custom" address, me@mydomain.com, - and set the outgoing server - in this case to pobox's smtp. So I have iCloud push mail with my own domain.... This works

On iOS 8, if I manually set up the iCloud as a generic IMAP email within iOS Mail app (so I can adjust the from address) - I lose push email, is this correct?

I have now found that if I do this with the CloudMagic App, then I can still retain push...... This works

The only issue I have now really is with WebMail access (this was formerly a feature in MobileMe - but only for a while). All email is also forwarded to a Gmail account for this purpose, but obviously I don't have such slick Calendar and iCloud Drive access....

Does anyone, perhaps with a developer account and a sneak into iOS 9 and iCloud know if the settings in iOS Mail app look like they might allow for own domain emails, while retaining push? And if iCloud.com might start allowing external emails addresses once again? Anyone know anything?

I would prefer to keep everything slick and inside Apple's ecosystem - I just like simple, as work around's are simply work arounds....