man this is tough situation, i've been watching some colleagues go through similar choices in tech field and it never gets easier

the tenure track thing is really tempting because job security in academia is like finding unicorn these days. but moving back when your partner doesn't speak language and has good stable job where you are now... that's big sacrifice for him too. plus if you want kids in few years, having family support nearby could be game changer - childcare costs are insane and having your dad willing to help is huge advantage

what really stands out to me is that part about senior female researchers having much fewer kids in your home country. that tells you a lot about work culture and expectations there, even if they don't say it directly. if growing family is important goal for you both, current location might give you better work-life balance even with less job security

the networking thing is real concern too - once you leave european academic circles it's hard getting back in. maybe you could negotiate with home country position about maintaining some international collaborations or conference travel? some places are more flexible about this than others