My wife and I got married a few years back and the plan was always to get her residency in the US and then citizenship and then move back to her home country. The more I think about it though, the more I don’t want to spend 3-5 years back there. For those who have spouses with citizenship, why did you do it? For those with spouses without citizenship, are there any benefits you’re missing out on based on them not having it?
In your case it seems there’s good reason to get her citizenship, at least she gets optionality. In the downside the taxes will be a pain in the rear, potentially.
Only case where I would hold back is for baby boys in certain cases, like my son who’s entitled to Greek citizenship. It’ll be up to him to decide if he wants to do a military service when he’s old enough to decide. And taking the small but nonetheless nonzero risk of being called up to fight Turks.