I tend to agree with you, but the writers are so skillful that I wonder how we'll see it initially, until we've had time to analyze it closer. They have always done such a good job of making Martin seem like the bad guy in the relationship, but we have figured out that Louisa has her issues. But I do think we saw him basically embracing a family life style in S5, taking care of family, home, and job in a very conventional way. Now he just needs to see to his woman, too!! and we'll all be happy.
I still am having some trouble sorting out what it means that Louisa will make or break the relationship between them.
Does it mean that she will be the one who decides whether it's working or not, and ultimately leave or stay -- assuming that Martin will not himself voluntarily make a choice to leave if it's not working? Because I think that's probably right. Despite his initial reluctance to commit to marriage, I think he's past that point now, and I just don't see him voluntarily leaving Louisa and James Henry, or issuing any ultimatums.
Does it mean that she is the one who now has to make some changes -- e.g., in the direction of greater tolerance, an acceptance of the things she cannot change, more flexibility about what she wants from her career and when, or where they live -- well, it seems right that she needs to make some attitude adjustments.
Martin has now offered the biggest change -- to give up on London and stay in Portwenn. But there's work he needs to do too, as in learning to operate like a partner instead of making decisions for both of them. So I can't let him off the hook entirely and feel that the issues that remain are up to Louisa to work on.
What I come down to is that they both have to alter some aspects of their behavior, but that Louisa needs to take the lead in verbalizing what she wants and needs from Martin and eliciting the same from him. Since left to his own devices what we have seen Martin do is either suffer in silence or explode, or make high-handed assumptions.
Of course, Louisa has not been exactly expert in handling communications between them either -- but of the two, I think she has more flexibility to alter her behavior and more willingness to change if she thinks it's necessary.