Not exactly; she’s a very good (future) partner, but I wouldn’t go as far as deeming “the best” candidate out of all the other women. I don’t like making a single RO that’s more important than the others (marriage-wise) because then the player may feel obligated to pursue a RO in particular to get a “good/perfect” playthrough.
Story-wise, though, Cora may be a better match than Lantana depending on which path the MC follows (the same can be said for Kalmia rather than Cora if the MC is thinking about joining the rebellion). A politically inclined MC (who wants to reform The Society from inside) might do better with Lantana, who is from the Purple Circles, has a title and is a very influential member of The Society, whereas if you’re more interested in only money and power, Cora is better suited for the MC’s schemes. Of course, they are not absolutes, so either three of them, or even Rhona and Cherry, will do for your playthrough if you make the correct choices over the game’s course
Oh, believe me, my plan is for the character traits to have a great deal of influence on how the ROs perceive and interact with the MC For example, Maynard likes stern and rational MCs that are not prone to touching him, whereas Maetthere and Cherry like sweet and caring ones
He’s… Complicated, and not even nice or a decent man (he has a lot of growing up to do), but I’m dying to know how will people react to him once romanced