I think there is also a huge diffrence between male and female authors and audiences tough.
Your suggestions need to be accounted for from the start of the novel.
Especially for male authors, because you can't write an emotionally dead novel and suddenly expect to be writing a good love scene, and let's face it, we men shy away from emotionally descriptive novels, and the few who dont favor depression, self harm and angst genres.
In my opinion, if love scenes are on the planning for future chapters, with a male target audience, then the author needs to be more emotionally descriptive from the start.
If a novel is not emotionally descriptive from the start, it is better to intentionally keep sex to smut only because a love scene even if we'll written in an emotionally dead novel just doesn't work.
Likewise, the genre of the novel needs to be considered from the start. Take 'The Mech Touch' for example which is primarily scifi engineering and design oriented.
It does well mostly because there is more emotion in it than most such genres as part of the design processes, and whilst a fantastic read and having emotion from the start, it is better to insinuate that there was sex than write a sex scene there because a sex scene wouldn't fit in the story when there hasn't been a shred of romance within the first few hundred, and by now thousand chapters.
So Target Audience, Genre, and Emotional levels of the story need to be considered from the start, to even determine whether there should be sex in a story at all, and if yes, if a love scene is even remotely viable as an option over smut if the story has had no or little emotional charge thus far.
But that's just my opinion, which many may differ on, but I believe is worth sharing and considering for male authors.