Re: multiple account holders that include non-residents
You'd have to ask the bank, it will be their policy that decides it.
I can't think of any disadvantages, except that the costs of using the Swiss account to do anything abroad would be horrible. It's hard to see the point for a partner who has banking needs in your home country.
It would be more cost effective to do an FX transfer via something like xe.com on a regular basis.
For visits - you can get a joint credit card, not sure how to do the cash part although surely just withdraw as needed.