I do think that the core relationships of the show would be different if Tommy had lived. Everything about the show would be different if Tommy hadn’t died. I can’t say whether or not Olicity would have happened when it did or at all if Tommy were still in the picture, but I do think that the Tommy/Laurel relationship would have always cast a shadow over any Oliver/Laurel relationship. There were always going to be three people in that relationship, and it was never going to work for any of them. I compare it to a more poorly written version of Rhett/Scarlett/Ashely from Gone With The Wind. As long as the specter of Ashley Wilkes was in the back of Scarlett’s mind, she could never wholeheartedly embrace a romance with Rhett Butler. There were always three people in their bed, said Rhett, and so it would have been for Laurel whether she was with Tommy or Oliver.
Sidebar: The book of Gone With The Wind is better than the movie, and the movie is pretty great.
Sidebar, part deux: Gone With The Wind had the perfect ending. As much as my heart of hearts wanted Rhett and Scarlett to work it out like the soul mates that they were to the extent that I dredged through the awful sequel, the “My dear, I don’t give a damn” line was so perfect.
Sidebar, part three: Seriously, though. The sequel to Gone With The Wind so bad. Don’t read it. I judge myself for having read it. I judged myself while reading it.
Back to Arrow!
As much as I hate to say it, I think that Tommy needed to die. Oliver needed unshakeable motivation to give up killing, and his oldest friend condemning the Hood’s methods for dispensing justice in one of their final conversations was pretty compelling. If the show had played to stereotype and killed off Laurel, Oliver would have had to mourn her. Her memory would hang over him in all of his subsequent attempts at romance, and that would have been a drag. Tommy’s death severed most of the strings that could have yanked Lauriver back together. In a way, Tommy’s death allowed for a clean break from the drearier aspects of Season 1.
That said, I’d be open to a retcon that Malcolm smuggled Tommy’s corpse away to Lazarus Pit him and has been keeping him hidden away for the past couple of years. I’m on board for Zombie Tommy.