My reading shows that there was was talk of an Eastern Conference at least as far back as the 1950's. In 1955 SU started it's long-standing series with Pittsburgh and West Virginia, restarted the Army series, (which for some reason, failed to become an annual event), and also scheduled Maryland, then a major national power. It was an effort to upgrade the program. Those schools replaced Villanova, Cornell, Fordham and Illinois.
I've always wondered how things might have been if the additional step of creating an Eastern Conference was taken then. It might ave included:
Syracuse
Boston College, (we played Boston University back then but they were on the verge of de-emphasizing)
Army
Navy
(Maryland was part of the newly formed ACC, which started in 1953 so I doubt they would have joined)
Penn State
Pittsburgh
West Virginia
and possibly, Notre Dame, which had no exclusive NBC contract at the time and was de-emphasizing the sport slightly after the Leahy Era and had a huge following in the Northeast, even more than other part s of the country.
Other possibilities: Virginia Tech, who had been left out of the ACC, Miami, which was a rising southern power.
Future possibilities: Florida State, (just coming out of the small colleges in 1955, sort of the USF or UCF of that time), Georgia Tech, (who left the SEC after 1964 due to a dispute with Bear Bryant), South Carolina, (who left the ACC in 1971 due to a dispute with basketball coach Frank McGuire and the conference), Rutgers, Temple, Connecticut, Cincinnati, Louisville. With some combination of those teams we could have gone to 12 teams when that got the conference a championship game when the NCAA rules allowed one in 1992. I'm not sure we'd have wanted to go beyond 12.
Syracuse, Boston College, Pittsburgh and West Virginia have been good basketball school, as have Temple, Cincinnati and Louisville. The others have been good in basketball at times.
I think it would have been a great conference and would still be in existence today.