Ok, thanks. Another thing to bring up with our looker rep.. 

Not sure if i follow, do you mean that we should include the base into multiple different models? OriginalModel.base -> Connection1.Model OriginalModel.base -> Connection2.Model If so, that would mean that they cant use the same reports, right?

User attributes cant change authentication method. So it wont solve our problem. (We want some users to use a service account, some to use oath)

That wont work if you want to have some users use Oath and some users use a service account. Is there a solution for this?

Is it really possible to extend the modelfile?