Morning,
To add wireless settings go to Chrome Management > Network > Add Wifi
We had to add wireless settings for both user and device to get around the "allow proxy on shared networks" tick box - This basically locks down the settings.
Where not using cloud print at the moment but I have had it working guide below might be helpful?
https://support.google.com/cloudprint/answer/1686197?rd=1
As to the globally branded theme I'm not sure but would be interested in this also!
Cheers