How I see it (I have a keeper alt that's into guys as well), is that for a Keeper it would very likely be shunned, because as you mention they are expected to be devoting time and effort into providing as many children for their clan as they can. What had mine going off on another trail is that he has a non-traditional upbringing, raised in Ul'dah after his mother made a break away from her roots to seek the larger cities and a more glamorous life. So in that he did not really know of his cultural roots, and certainly isn't finding them to be ones he'd want to live by. Still, the family he still speaks with regularly (siblings) heckle him - albeit not with scorn, more endless teasing and stern talking - about putting children into the world. If the rest of his sub-clan were alive/if he was speaking to them, it'd probably be a lot worse. For a more traditional keeper I would imagine it would be in their clear interest to keep things low-key.Â
As for seekers, their burden is also one to set children into the world once they take the mantle of Nunh - so there's a similar problem here, in that if they're not interested in doing that they would probably not be a Nunh at all. As far as I understand, Seeker Nunhs have to convince their females to stick with him which is largely done by proven the stronger one - for better and stronger offspring. They might be fine with just being a Tia for life, and if that is accepted by their tribe or not - I reckon that is a thing the individual tribe might determine, as there are things that suggest the tribes are culturally very different. For a seeker I don't think the internal strife would be as bad as that of a keeper.Â
As for cross-clan romance, I believe that is a widespread taboo, with mixed-children in Seeker Tribes being rejected/cast out if discovered and such. The less traditional your Miqo'te and their family is the more open they might be to something like that.
As for seekers, their burden is also one to set children into the world once they take the mantle of Nunh - so there's a similar problem here, in that if they're not interested in doing that they would probably not be a Nunh at all. As far as I understand, Seeker Nunhs have to convince their females to stick with him which is largely done by proven the stronger one - for better and stronger offspring. They might be fine with just being a Tia for life, and if that is accepted by their tribe or not - I reckon that is a thing the individual tribe might determine, as there are things that suggest the tribes are culturally very different. For a seeker I don't think the internal strife would be as bad as that of a keeper.Â
As for cross-clan romance, I believe that is a widespread taboo, with mixed-children in Seeker Tribes being rejected/cast out if discovered and such. The less traditional your Miqo'te and their family is the more open they might be to something like that.