I picked the customise multiple aspects option, but not sure if that’s best for me . I don’t like it when npcs gender and what not can be changed. I have previously played gueneveire and divided we fall with set ros(though in divided we fall if I remember correctly you don’t have to be in a relationship, but only have one option if you do, but don’t quote me on that, has been ages since I played it).
In both those games I don’t like as such the RO. In divided we fall he’s aligned with one of the fascist wings(sorry my knowledge of the Spanish civil war is limited and yeah haven’t played it in ages ) and in Guen Arthur is nice…too nice, so I don’t dislike him, but he’s a million miles from my mc . But in both those games the RO is well fleshed out and interesting. So I think it’s important that even if you don’t like the RO as such that their character is interesting and well developed.
But also yeah having multiple options of how the mc can feel about the RO is important too, and you should be able to romance other characters later on, or there should be a good reason why you can’t. For example in divided we fall you play different set characters, but the mc who can go with the fascist has little opportunity for romance due to the war and her role in it, and in guen you can romance other npcs, but have to stay with Arthur(I think) at least officially to remain queen.
I think also having a set RO has one of the same advantages as having set mcs or interactive novels rather than game books in that you can explore the set RO in more depth than if they were just one of several other ROs. Of course that can be a disadvantage too I guess, as since they are more prominent there is more pressure for them to be interesting and well written, but if their presence is significantly more prominent than the other ROs presence then that is true even more so.