The Massachusetts Gaming Commission, which began comparing the two companies vying for a Greater Boston casino license on Monday, raised concerns about the design of the proposed Wynn Resorts hotel tower in Everett and voiced strong reservations about the marketing and financing of the Mohegan Sun proposal for Revere.

The reservations about the Mohegan Sun proposal seemed serious. Commissioner Enrique Zuniga, who was charged with leading a team looking at the finances of the two casino developers, said Mohegan Sun had failed to realize the potential of a Boston casino to attract customers from outside eastern Massachusetts. He implied that Mohegan Sun may be more interested in protecting its flagship Connecticut casino than promoting its proposed Massachusetts operations.

Zuniga said the Mohegan Sun proposal is focused primarily on attracting local customers with its heavy reliance on slot machines and mid-priced hotel rooms. He said his group’s research indicated Mohegan Sun, despite its familiarity with the New England market, overstated the size of the local market in Massachusetts by close to $50 million. He said Mohegan Sun is expecting to bring in only $40 million from outside the eastern Massachusetts-southern New Hampshire market, with most of that $40 million coming from western Massachusetts and Connecticut.

By contrast, Zuniga said Wynn’s preference for more table games and the company’s plan to build five-star hotel rooms is expected to attract visitors from all over the northeast. He said Wynn expects to bring in more than $230 million from outside the eastern Massachusetts region, including $75 million from international visitors and more than $50 million from tourists. “Their market view aligns with the state’s chosen casino model,” Zuniga said of the Wynn plan.

Zuniga also raised serious concerns about a marketing agreement between Mohegan Sun’s operations in Massachusetts and Connecticut. Mohegan Sun officials have said the agreement is designed to protect the proposed Massachusetts casino by barring the Connecticut casino from marketing to customers near the proposed Revere facility. But Zuniga said the agreement actually offers little protection. He said it requires the Connecticut casino to supply to the Massachusetts casino the names of all customers in its database who live roughly within Route 495. But it only bars the Connecticut casino from spending more marketing to those customers than the Massachusetts casino spends; outside of Route 495, the Connecticut casino can spend as much as it wants marketing to Massachusetts customers.

As one of the conditions of receiving a license, Zuniga recommended that Mohegan Sun extend the marketing arrangement to all of New England and put the commission in charge of monitoring the marketing agreement.

Zuniga also raised concerns about Mohegan Sun’s financing plan. He said it is heavily reliant on debt that is not secured by physical assets, suggesting that lenders may become nervous about loaning so much money to Mohegan Sun. He urged his fellow commissioners to order Mohegan Sun to come up with $100 million more from investors to reduce the debt-to-equity ratio of the project.

Zuniga noted the Mohegan Sun proposal exceeds the minimum $500 million construction investment requirement only by including its leases for gaming equipment. By contrast, Wynn plans to spend more than $1 billion on its facility, which Zuniga said not only satisfies the minimum spending requirement but also will insure more construction jobs at the Everett site.

The report from Zuniga also shed light on the financial relationship between Mohegan Sun and Suffolk Downs. Suffolk Downs had initially planned to operate its own casino operation at the track, but when East Boston residents voted the proposal down the track invited Mohegan Sun to lease a portion of the track in Revere for a casino. Suffolk Downs and Mohegan Sun have described themselves as landlord and tenant, but Zuniga portrayed the relationship as a lease-partnership.

According to documents presented by Zuniga, Suffolk Downs would receive rent payments of about $35 million a year that could rise to between $75 million and $85 million a year based on the gross revenues of the casino operation. Zuniga also said Suffolk Downs had put up $70 million in equity in the casino and stands to receive more than 5 percent of any distributions to the owners of the facility.

James McHugh, another commissioner, reviewed the building and site designs of the Wynn and Mohegan Sun projects. He gave fairly high marks to both projects, but raised concerns about Wynn’s traffic mitigation efforts at Sullivan Square and was very critical of Wynn’s proposed bronze-glass design for the hotel tower. He said the approach works well in Las Vegas, but may not be suitable for New England.

Noting the Wynn design is virtually identical to a proposal the company presented briefly in Philadelphia, he said: “It is a generic design, clearly. It doesn’t capture the energy that this company is capable of.” (It’s not a money issue, since Wynn is spending roughly $635,000 per hotel room while Mohegan Sun is spending $220,000 per room, McHugh said.)

McHugh strongly urged Wynn to come up with a new exterior design for a project that he said will be the first major building visitors to Boston will see driving in from the north.

In other presentations to the commissioners, agency staffers said Wynn’s overall financial performance is currently much stronger than Mohegan Sun’s. They said neither developer has any suitability problems to worry about, although they said Mohegan Sun may be in technical violation of its contract with a partner in an earlier casino proposal for the town of Palmer. Mohegan Sun has been accused of jumping ship to Revere when the going got tough in Palmer; agency staffers said Mohegan Sun started talking to officials at Suffolk Downs shortly after losing a referendum campaign in Palmer but before its exclusivity agreement had ended there.

The Gaming Commission plans to continue its review of the two casino proposals Tuesday and Wednesday and hopes to choose between Wynn and Mohegan Sun by Friday.