OK, so when Pidgeot goes, there will still be Search powers in Colorless, such as Persian and Porygon 2, not to mention Delcatty. There will also be Dark Powers like Mightyena EX and Shiftry EX, Umbreon EX and more. Plus plenty of Metal powers from Starmie Metal Navigation to Gardy's Energy Jump and all the Delta Species. So Battle Frontier isn't going anywhere.
That means Magcargo and Jirachi will dominate (for a while, until something better comes along). Girafarig will be meaningful for a time to counter Mr. J. And Lunasol may see some action to stop Cargo.
Perhaps Lapras will become a necessity. But Medicham, Muk, and Pidgeot D (plus new anti-Power cards) will likely make life tougher here also.
Eh.... it's all academic anyway. Let's play out this season first, not worry about next format. There will be at least one set out before Cities anyway, and MC is going to make the game kee-razee! (the way I like it)