I don't think facilities differences were a major factor in Kim English's decision. The primary problem for Mason was that the Friars offered KE a life-changing amount of money with which Mason could not hope to compete. If another company offered you 3-4x your salary, would you stop to ask your current employer for a nicer office before deciding? I know I wouldn't.
As for keeping pace with the Big East and their massive media contracts, that's just not realistic, unless someone on these boards wins the next billion dollar PowerBall jackpot.
Edit: All that said, there's a huge gap in between "build a Big East-caliber facility" and "do nothing" and I certainly think some upgrades should be in the plans, if they aren't already.