Sorry but I don’t understand the problem: you have British citizenship. You can reside and work anywhere in the EU. That puts you in a fairly enviable position. If you marry your wife is entitled to permanent residency (I think it’s called permanent leave to remain), which is a lot easier to get than say any US equivalent. British permanent residency is (for now) EU residency.

It’s also not quite true that your children would be stateless. This vastly depends in where they’re born. Also there are provisions for this in UK law. Lastly grandchildren of UK born citizens (which it sounds like they would be) are entitled to an ancestry visa. This gives 4 years to live and work in the UK without restriction. If they’re still there after 4 years they then get permanent residency and are entitled to apply for citizenship a year after that.

EDIT: so it’s been some years since I lived in the UK and the rules have gotten much harsher on spouse visas, namely there is an income requirement for the Briton (£18,600pa) and the spouse visa is for 30 months renewable for another 30 months so now it takes 5 years to get ILR (indefinite leave to remain). It used to be 2.

Still, it’s an option. As are other EU countries. Ireland, Sweden and even the Netherlands look like decent options. Maybe Austria too.