With the CityLab Detroit conference concluding Tuesday afternoon, it’s worth a moment to consider what emerged from it.

Start with the numbers. Sponsored by The Atlantic magazine, Bloomberg Philanthropies and the Aspen Institute, CityLab saw about 600 people from 156 cities and 26 nations attend the conference at the Detroit Marriott Renaissance Center.

They heard dozens of speakers and they embarked on field trips to a variety of Detroit sites including Eastern Market, the Fitzgerald neighborhood on the city's northwest side, and the downtown real estate world of businessman Dan Gilbert.

For those who followed the three-day event in detail, it was like drinking from a fire hose. But distinct themes and conclusions did emerge by the time all the out-of-towners took their shuttle buses to the airport.

Here are seven of those themes:

1. Amazon HQ still rankles

Even the cities like Detroit that tried in vain to make the short list for Amazon’s second headquarters have mixed feelings about the feeding frenzy. Detroit offered Amazon $4 billion in tax incentives to bring its 50,000 workers and billions in new investment here.

The common feeling at CityLab is that those huge tax breaks that cities were throwing at Amazon left a bad taste almost everywhere. Some felt the “losers” had actually dodged a bullet. Seattle Mayor Jenny Durkan noted that Amazon’s impact on its hometown has been a mixed blessing, bringing new employment but driving up home prices and driving out more modest-income residents.

And many expressed a desire to see all that tax-incentive cash better directed toward improving schools, public transit and other urgent needs.

2. Scooters are controversial everywhere

The new electric scooters that turned up in Detroit a few months ago have proved contentious in many places where they’ve been introduced. Some mayors pointedly buttonholed Scott Kubly, an executive with the Lime scooter company, for introducing scooters into the public right of way in a fashion that many mayors seemed to resent.

Kubly acknowledged the tensions, telling one group, “If we don’t deal with the negative externalities we create, they will be regulated.”

Surprisingly, one of the biggest fans of the scooter revolution was Detroit Mayor Mike Duggan, in part because they reduce the need for private automobiles. “Every time there’s somebody on a scooter, that’s not a car on the road,” he said. “People love them. It has become integrated into mobility.”

3. Detroiters get starring roles on bigger stage

Duggan, by the way, spoke several times at CityLab, proving a popular draw. Former New York City Mayor Michael Bloomberg, who cosponsored the event and opened the conference, praised Duggan as among America’s best mayors, and Duggan’s story of the city’s partial turnaround won nods of appreciation.

But Duggan wasn’t the only Detroiter to take center stage. Dan Gilbert talked about the rapid expansion of his Quicken Loans family of companies downtown. City planning director Maurice Cox outlined the city’s plans to revitalize neighborhoods. And well-known entrepreneurs like Kristen Ussery of Detroit Vegan Soul and April Anderson of Good Cakes and Bakes told their stories.

To the Detroiters in attendance, the familiar faces had an air of “Detroit’s greatest hits.” But to the hundreds of outsiders, it proved a great introduction to Detroit’s recent story.

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4. Data drives everything

If there was a single theme to CityLab Detroit, it was how the intelligent use of data will increasingly drive decision-making for cities.

That data comes from everywhere — from traffic patterns and school graduation rates to health care outcomes and poverty and employment rates. Data gurus are pooling all manner of data and packaging it for municipal leaders in a way that will help them map out solutions to urban problems.

But everyone agreed there’s a danger to using data algorithms to make key decisions unless real humans remain in charge. And the public needs to understand how the data systems work. That doesn’t always happen.

“Urban data really ought to be a public asset managed by a public trust,” said Dan Doctoroff, founder and CEO of the consulting firm Sidewalk Labs.

And Andrew Nicklin, a data expert with Johns Hopkins University in Baltimore, added, “We’re transferring power from people to technology but we’re not vetting technology like we do people.”

5. Racism still dominates, especially health care

David Williams, a professor at Harvard University, outlined a series of fascinating statistics demonstrating that racial disparities still impact all aspects of our lives, especially health outcomes. People of color who live in racially distressing environments see higher rates of hypertension and multiple other ills.

“Our bodies keep a record of all the experiences we have,” he said.

The takeaway: Those who wish to believe that America is over its race problems need to pay more attention.

6. Who wasn’t there was notable

Since CityLab is designed to help mayors better govern their cities, the attendance list was top-heavy with municipal government leaders and consultants. Inevitably, that left out a lot of people who may have contributed.

Most notably, those not there included a lot of neighborhood nonprofit activists, the sort of people who run the community civic groups that have done so much good in Detroit against very difficult odds.

And many of the solutions offered at CityLab will inevitably be implemented at the City Hall level. There’s a whole universe of other actors — in neighborhood organizations, in philanthropy, at the corporate level — that can and will play an equally significant role in Detroit’s revitalization efforts.

7. Improvement is possible, despite obstacles

Despite the multiple problems that continue to dog Detroit and other cities, progress is possible, and Detroit showed everyone how it's done. It requires dedicated work by players at every stage, from teachers and shopkeepers to mayors and corporate executives.

Detroit showed how a bankrupt city could emerge from decades of decline and abandonment to see a fiscally healthy city hall, a revived downtown and shoots of progress even in many hard-hit neighborhoods.

If Detroit’s story on display these past few days at CityLab proved nothing else, it’s that intelligent effort equals results. It’s just that we still have a long way to go to build what Maurice Cox called “one of the most inclusive recoveries this country has ever seen.”

Contact John Gallagher: 313-222-5173 or gallagher@freepress.com. Follow him on Twitter @jgallagherfreep.