The Pistons are faced with a critical offseason that could present some big changes — or just a couple tweaks, as coach Stan Van Gundy said — to look to get back to the postseason next year.

Although they improved defensively this season, their offense lagged behind, ranking 28th in 3-pointers (33 percent), 26th in scoring (101.3) and 22nd in field goals overall (45 percent). Part of the struggles were due to Reggie Jackson missing 30 total games and just some poor shot selection and execution.

That’s something Van Gundy is looking to improve next season, with an eye on getting more players involved — and in different ways. Kentavious Caldwell-Pope, who will become a restricted free agent, shot 35 percent on 3-pointers but just 40 percent from the field. It’s the best he’s shot from long range in his career, but still better than the rest of the roster.

“I think we can do a lot of work beyond just tinkering and take a good hard look at what we’re doing offensively system-wise to fit our players a little better and get us more quality shots,” Van Gundy said last week. “If you look at it from an analytics standpoint, the shots we were getting, some of it is the product of the players we have out there, but some is the system too.

“We didn’t get enough lay-ups and we didn’t get enough 3-point attempts. They come hand-in-hand.”

Van Gundy said before the season that the Pistons were looking to be less reliant on Jackson and that seemed to be the case in those first 21 games. Caldwell-Pope was averaging 15.2 points and shooting 40 percent from beyond the arc. Those numbers fell to 13.8 points and 35 percent by the end of the season.

Tobias Harris was at 17.1 points and 37 percent from 3-point range in the first quarter of the season, but that dipped to 16.1 points and 35 percent on 3-pointers for the season. It’s not saying that having Jackson on the court hurt their numbers; rather, the Pistons were figuring out ways to make up for Jackson’s absence.

They seemed to adjust to having Ish Smith as a pass-first point guard, but when Jackson returned, they had to re-align to his high-volume handling and shooting style. Moving forward, they’ll look to get more players involved, including 7-foot-4 center Boban Marjanovic. Van Gundy was hesitant to play Marjanovic because he viewed the big man as a defensive liability.

Now, Van Gundy seems to be coming around on his thinking and looking to give some of the reserves more opportunities to show what they can do, especially Marjanovic, Stanley Johnson and Jon Leuer.

“The playing time thing is to open it up and see who gets minutes. As far as summer work, our offensive system needs a lot of scrutiny,” Van Gundy said. “I have a list of other coaches and what they do and concepts that fit us.”

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