I was going for having it look just like a highway sign, with the exception of the Mets script, of course. I even found the font that the highway signs use!
How about "Grand Central Mets"? The 7-Line has co-opted the name of the subway that goes to Shea, I mean, Citi. We could do the same with the highway that goes there. It also suggests that the site is a hub of activity.
I'm noticing that the Cubs site (North Side Baseball) and the Marlins site (Fish on First) does not incorporate the team name:
About DiamondCentric - DiamondCentric
DIAMONDCENTRIC.NET
And the sites for the Blue Jays (Jays Centre) and Red Sox (Talk Sox) only include a partial team name. So the question becomes, how critical is it that the site include the word "Mets"? Or could we call it "Flushing Baseball" or "Who's on Third?"