Most Northeastern cities have at least one small suburb that if the city was removed completely, the town could go on just as well without it.
One example is my former home of Emmaus, Pennsylvania, population 11,000.
Emmaus is an inner suburb of Allentown, a city of ~100,000 located in eastern PA, about an hour up the turnpike from Philadelphia.
In this three square mile town, Chestnut Street (aka Main Street) is the main street and has businesses up and down both sides. State Street is also commercial and there are a few businesses on Harrison Street. Everything else is residential.
Housing is mainly a mix of row homes and single family homes, built between 1860 and 1990 and costing between $100,000 and $300,000. No one is really rich and no one is poor.
It seems like there are just enough people in town to support at least one of everything necessary, and much of it it is independent businesses - a furniture store, appliance store, coffee shop, movie theater, etc. You could easily buy everything a typical family owns without leaving town.
Major employers are almost all nearby companies, not in the city. More people work right in town than in any city. Average commute is 19 minutes but that is skewed by the people who drive over an hour to Philadelphia or New York/North Jersey.
Emmaus is right on a major interstate and is obviously convenient to Philadelphia and NYC, which is where people from this area go for "big city" attractions anyway.
A large industrial corridor is nearby and consists mainly of warehouses for NYC and Philly companies. Obviously that could exist without the central city.
Quite a few farms are south of town, though that won't be true for long.
The town is almost all flat but some areas really close to the main street are quite hilly with winding roads. Golfing is in town and skiing is not ten miles away.
Which other small suburbs could function well if you removed the city? Perhaps some people work in them.