As for NI, I'm totally in favour of no border and telling the EU to propose a solution. Instead these UK negotiators are doing the job of solving EU issues. For the UK a no-border is obligatory for all the good reasons, if the EU doesn't like it then they should dream up some sort of solution.
Firstly, one of the main themes of the Leave campaign was control of our borders. So, having "no border" between NI violates that. It would also allow free movement of people from the EU to the UK, as there would be no border between the EU and Eire, none between Eire and NI, and none between NI and UK.
Secondly, do there already is a border, and will continue to be a border, no matter what happens. It's all about how "hard" that border is: It's currently virtually non-existent for all practical purposes.
Thirdly, we don't have autonomous control over our border with another country: They have a say too. While ever Ireland is in the EU, the EU has a say. They are not going to let people and goods flow freely from a third country with different standards into an EU country (from which they can flow freely to the rest of the EU). Nor are they going to compromise their security by allowing people to move freely (as mentioned in the first point, it would effectively allow free movement from UK->NI->Ireland->EU).
Finally, on to your point about the French unemployed, this will end anyway. Ending free movement is one of the govt's red lines. Unless we back down from that one (e.g. remain within the EEA/EFTA) that's not even on the table.
I still don't understand why people think the EU needs a deal more than the UK does. We are a small country. We may punch above our weight, but we are still tiny compared to the EU. In terms of the value of trade as a proportion of the total value of the economy (or per head of population), we need a deal far more than they do. We will suffer far more damage than the EU without a deal, and we don't have any serious other deals on the table yet. Even those in the pipeline have shown that other countries are quite willing to press for very good terms in their favour as they know how much we need to have sone form of trade deal.