1) Jayson Tatum's development on defense and with his body. He should already have the offensive skills to potentially be the top scorer off the bench but I want to see progression that shows me that he can be on the floor at the end of games as the season progresses.
I also want him to be a viable option at PF in the future, so playing good D and bulking up at a reasonable pace are important. My dream is Tatum getting a few starts at PF late in the year.
2) Who emerges as the starting SG? I'm interested in Brown's development next year, so if it's him, and I hope it is, how does he function within our offensive flow with increased minutes.
If Smart starts and JB comes off the bench, then I want to see how offensively dominant JB is on a bench unit with Rozier/Tatum/?/Baynes, and how good that unit is league-wide.
3) As someone mentioned, I want to see the Kyrie-Horford pick and roll. Horford sets great screens and has the skills and veteran IQ to know when to roll and be good at it, and we all know he's got the pick and pop skills. Kyrie is about the best scorer in the world taking 5-7 dribbles or more, so he should be deadly if looking to score. I'm hoping his passing improves.
With the Kyrie-Horford PNR, Morris should be a fantastic option as a spot up guy in the mid range or the far corners to keep the defense honest and stretch it by fully opening up the paint. And I want to see how Hayward and hopefully Brown, my ideal starting SG, work together off ball to get each other open and allow each other to get to triple threat spots for a Kyrie dish.