Honestly, the writers are aware that the densi fandom will not be happy if they mess up densi because of Sullivan.
What will they do? Make kensi cheat? Make kensi fall in love with Sullivan?
I seriously don’t see what the writers can possibly do and I also think if they were going to mess up densi, they would have done it in season 6. Not now. Kensi and Deeks have come to far.
So I’m not worried about Sullivan. Because I trust the writers right now, at the moment.