They need Fultz to come through, absolutely, and better guard play in general.

If you stack the inside though, this team can make you pay. Reddick and Saric can both shoot, they have some other adequate shooters, too. I think outside shooting is no longer a major issue for the Sixers, it's more having a guy to handle the ball to protect leads late in games and also having someone who can run the second unit (or being able to split Embiid/Simmons up a bit more, which another star would do).