I think it depends on the year, and how strong Central is. The past 8-10 years Central was just another local team that Meigs wanted to beat. This season being a Region game, and Central being much better, and the winner of their upcoming game probably being the Region champ, I'd say Central probably is Meigs' biggest rival. Vice-versa, Meigs is probably Central's biggest rivalry this season.
Having some solid teams that are relatively close to each other is actually good for making it a stronger rivalry and Region.