Let's talk money.
Are you keeping Gallo next season? How much do you intend to pay him? Or do you think he just stays for his players option? Are you keeping Olynyk? In terms of Gallo and Olynyk, how much are they going to have in salary for the 2018-2019 season?
That last question matters, because now you have IT, Bradley, and Smart hitting free agency, and you have a decision to make on Jokic. You can decline his option and make him a restricted free agent, or you can keep him at his low salary for another year and hope that he doesn't leave you in unrestricted free agency. Since we've traded the Brooklyn pick for Jokic, he's getting the max. IT is getting the max. If we've kept Gallo and Olynyk, along with Horford and some other salaries (Crowder and Brown) we're probably well into luxury tax territory before even talking about Smart and Bradley.
Accordingly, if you're going to let Gallo walk next summer, he shouldn't be in the deal. And then it's a straight up Brooklyn pick for Jokic trade. If you're going to let Olynyk walk because you're keeping Gallo, he should be in the deal with a lesser pick. Signing both of those guys next summer is going to cause a lot of pain in 2018.
The prize of the deal is Jokic. I also like the fact that his salary, at least for the next 2 seasons, would be significantly less than that of the #1 pick. Those savings could be plentiful in giving Hayward the max.
As for Gallo, I would be perfectly fine in letting him walk. I do think he could really help us out the rest of this season. However, him getting minutes at the 3, along with Crowder already in place, would potentially stunt Brown's growth. The investment in Brown is too great to risk it on Gallo.
Hayward can play either the 2 or 3 spot and I really like him at the 2. Like DeRozan, who has a big size advantage over the majority of 2's, Hayward can really take advantage of his defenders there. At the same time, this would appease Crowder. So, yes, in this scenario I would have us trading away Bradley in needed.
I understand what the prize is. What I'm saying is that the money is trickier than you're giving it credit for. You're giving up the potential #1 pick in the draft for Jokic -- you can either make him a restricted free agent in 2018 and max him then, or wait until 2019 when he's an unrestricted free agent. He's a savings next year over the pick, but that savings is short-lived.
Let's take your plan of getting Hayward in July, and either trading Bradley or letting him walk (I vote the latter, because he's a good player and would provide injury insurance in 2017 for either Hayward or Crowder, since Hayward could slide to the 3 in such a scenario.)
In 2018, if you make Jokic a restricted free agent and max him, and max IT, you would have $128.5 million committed to just 6 players -- Horford, Hayward, Jokic, IT, Crowder, and Brown. The luxury tax is forecast to be $129 million. We haven't talked about Smart yet, and we've assumed Bradley is going. Then there's the 2018 Brooklyn pick, Zizic, Yab, and Rozier. None are that expensive -- collectively it's about $12 million. But it's very easy to see the teams salary hitting at least $154 million if you keep Smart. That'd be a luxury tax bill in excess of $63 million for a single season.
So instead you could not pay Jokic in 2018. There'd likely be a small luxury tax bill, but it'd be manageable, and you could keep Smart. But you're just kicking the can down the road, because Jokic is getting paid in 2019, and none of the above players are coming off the books. Or Jokic decides to leave because he's mad he played for an extra season at the minimum salary when you could have made him a free agent.
So you could make the trade, but you'd have your desired team for at most a season and a half before it started to become prohibitively expensive and losing key pieces, and maybe several. Do you think you're winning a title this year with that team? Next? You have to be really confident that you are, and I'm frankly not. I'm confident it would be better, but not better enough.