Stan Van Gundy looks at his roster, sees the ages of all his key players and expects improvement. He understands it isn’t inevitable, but he’s seen nothing this summer to dampen his enthusiasm.

And he’s seen a lot. There’ve been no real vacations for Van Gundy, balancing his duties as both Pistons coach and president of basketball operations while also mixing in a little family vacation time on his tours of the country to catch up with Pistons players. He’s spent time in Southern California watching Andre Drummond, Stanley Johnson, Reggie Jackson and Reggie Bullock train – caught Dodgers, Angels and Padres games with his son, Michael, for good measure.

A weekend in New York – took in two Broadway shows with oldest daughter Shannon plus the taping of “Last Week Tonight” with comedian John Oliver, son-in-law of Palace Sports & Entertainment president and CEO Dennis Mannion – meant spending time with Tobias Harris at his Long Island base. Swung through Philadelphia – got to see old friend Fredi Gonzalez, former manager of the Marlins and Braves – and caught up with Marcus Morris.

He’s liked what he’s seen from all of his players. But he cites two as having the greatest potential to take noticeable steps forward in the 2016-17 season.

I asked him about the strides Andre Drummond has shown but still needs to make as a rim protector. Van Gundy acknowledged the ups and downs – more on that in a minute – and in the course of answering, said this: “Look, he’s the guy – probably he and Stanley (Johnson) are the guys who can, I think, based on their age and what they’ve done and what they’re capable of doing, who have the potential to make the biggest jumps.”

Drummond made the All-Star team as a 22-year-old last season and led the NBA in rebounding (14.8 per game) while averaging 16.2 points. Johnson was the team’s sixth man during a rookie season in which he averaged 8.1 points and 4.2 rebounds as a 19-year-old.

The Pistons will have the NBA’s best depth chart at center with Drummond backed by Aron Baynes, coming off a rousing Olympic tournament with Australia, and free-agent addition Boban Marjanovic. But Drummond’s role isn’t likely to be diminished from the 33 minutes a game he played in his fourth season.

For a second consecutive summer, Drummond spent the bulk of it working at the Santa Barbara, Calif.-based P3 training facility. He’ll come to camp stronger and in better condition than ever and is expected to continue showing off a maturing offensive post game. He’s also focused on addressing his .355 free-throw shooting performance with improvement necessary to allow Van Gundy to use him in the face of intentional fouling tactics.

Less discussed but just as critical for the Pistons will be an increased menacing presence around the rim. Van Gundy saw progress in the postseason series with Cleveland after ebbs and flows as a shot-altering threat over the regular season.

“He’s still so young, but he’s been in the league long enough,” Van Gundy said. “He’s got to really just do what it takes on the mental level to get himself ready to play every night and get himself focused at that level and that hasn’t quite happened yet. Now, it’s improved every year, which is good. But he’s not quite there all the time to where he’s ready to go.

“I thought in the Cleveland series, he played with that attitude of challenging shots and making it tough around the basket and he sustained that pretty much throughout the four games. If he does that, then he makes a big jump with our team.”

Van Gundy quickly came to view Drummond as the centerpiece of the franchise upon taking over in May 2014 and he hasn’t wavered from that position for a minute since, fully endorsing the organization’s decision to commit to a maximum contract that will keep Drummond with the Pistons at least through the 2019-20 season.

“Andre’s worked really hard. I think he did a pretty good job last summer; I think he’s added to that this summer in terms of being disciplined in his approach and working hard. I think he’s taken a different approach to his free-throw shooting. He’s really worked hard on some of his other areas.”

Van Gundy said Johnson had a solid stretch of skills development early in the off-season and through Summer League. That stalled as he switched to a different mode for his week with the USA Basketball’s Select Team, but Van Gundy expects a strong finish to his off-season and a more focused Johnson for training camp.

Johnson is notoriously confident and headstrong, which Van Gundy admires – while admitting it presents a coaching quandary.

“It’s an ongoing challenge, for him and for us. But the strength Stanley has is he’s got a tremendous passion for the game and tremendous desire to be great. He’s as good a competitor as you’ll find in this league, as young as he is. What goes along with that is a stubbornness, to some degree. At times, I’ll be honest – working with him can be a little bit frustrating because of that. He thinks he knows the way to do it.

“But also what goes along with that is a guy who just doesn’t give in easily in games, either. He’s just not going to give in. He’s a tough guy. I’d rather have it the way he is than a guy who let’s say is 100 percent compliant but doesn’t get out there and really fight like he does on the court. Everybody’s a little bit different and everybody’s got different strengths and different weaknesses. His tough mind is his greatest strength and at times can be his … I won’t even say his greatest weakness, but it makes him a challenge to deal with. But he’s a tough guy out there and we’re happy to have him.”

The Pistons went from 32 to 44 wins and a playoff berth last season while figuring it out on the fly with a team of relative newcomers. They have the potential to make a similar leap forward in the season ahead with everyone of any impact on the roster still on a career upswing. No two players have greater potential for that arc to rise faster than Andre Drummond and Stanley Johnson.