I agree, and it's always a bad idea to kill off a character's only child.
If Steffy had to accidentally kill someone it would have been so much more dramatic and opened so much more storyline possibilities if it had been Hope.... With their history, the long, complicated history of Taylor/Ridge/Brooke, and add to that Rick's part in Phoebe's death, it could be an explosive story that could go on for years.
You could add the unlikely friendship between Stephanie and Brooke during the later years. I know Brooke always wanted Stephanie's approval but after everything that happened between them and everything they did to each other it was a bit far-fetched that they would ever become good friends.
None of them was dragged into the relationships screaming, against their will. And they were all grown-ups, perfectly capable of making their own decisions. Yet Stephanie always put all the blame on the Logans (or Sheila or Lauren).
I think Storm didn't exactly endear himself to Stephanie when he shot her though....
As for the rest of the Logan family they had ample reason to hate her right back, especially Brooke. She tried repeatedly to bury the hatchet with Stephanie, but she wasn't interested unless she could bury the hatchet in Brooke's back.