Brother, divorces in real life are not at all pleasant or easy but only for men who made this religion for their own ease. The so called real life is actually MAN made No 2 Islam by-product. The more one comes towards the truth the more it becomes obvious. And all this is what Allah wants from all of us not man of course!
Allah SWT is telling just the opposite; to resolve all the matters amicably even the divorces, fearing Allah all the way. The stress is on men as they always tend to be more unjust. Well as they say power corrupts.
So in truly Quranic system, all matters including those of kids should be resolved fairly by mutual agreement so none of the parties suffers.
As for lewd behavior, the punishment is for all and once proven only. So that should apply to even those who are married.
If a person then still wants to keep her as wife forgiving her then what else is required?
If not, then he has the case. But I think once punished and for those who mend their ways that should be no longer held against them as an excuse as Allah is always forgiving and merciful, and this is also being reminded here. So, all matters should still be decided justly.
Finally, I think yes, the way the words have been used here; it seems Allah clearly does not want any one to doubt that the previous verses were NOT about multiple marriages.
And I did not understand the first line. Having an insight “being a sister” means what, can you please explain?