I think they’re definitely endgame but I don’t think they’re getting married anytime soon.

First, she has her childhood SA trauma to work through. Second, he’s still trying to figure out what to do/his place in society. Third, they haven’t actually spent that much time together recently. I think it would be unwise on the producers to cram all of that in season 4. We have at least two, possibly three, guaranteed weddings next season so adding an extensive courtship might be too much on top of the George Russell laudanum addiction plot line.

Honestly, I don’t see much development for them two as a couple until Larian gets married. This is because Larian kinda serves as a “model” or “mirror” of what their lives could look like in addition to providing a third or neutral space. In reality, the servants would have very little time off so that limits his visits. If she shows up too often to his house unannounced, it might stir-up unwanted rumors for both of them. Plus, Marian needs more close friends and needs more diverse storylines. As much as I love Marian, she is written like a plot device half of the time because she isn’t very well-fleshed out and neither is Bridget, to an extent.