Which is better, creating a new account (and use referral code etc.) for spouse or add her on my account?
I would think it is better to have separate accounts. Obviously the referal is one reason (why not), but also, gives you more flexibility in the future.
But that is more of an opinion. Everyone is different :)
I know for kids accounts, people create all on one account and then realize when kids leave the house that they need to port out their numbers to another provider, since they can't just move it from one account to another and keep their numbers within Fizz (at least not for now).
I was asquing myself the same question but finaly my husband open is own account I think it's better that way. You can controle the account if you want or let the other do it. And over that you'll have both the reference bonus.