I stated a long time ago that FF7's Midgar is pretty much a direct rip off of ToP's Midgard in so many ways, such as Mystek and Mako being similar, the existence of a super cannon, the fact that the City stands out as far more urban than anything else in the world, etc. The only real difference is that Shinra is generally portrayed as Antagonists while Midgard is generally allied to your team (while not being strictly good, but that gets into ToP plot specifics), so plot devices vary and what not (In ToP, Midgard pretty much goes "Hey, join us, we could use your help against Dhaos!" and the team generally agrees outside of Arche, IIRC, who more had reservations but ultimately gives in, where as in FF7, you get a robotic cat as a spy shoved into your team...)
Its possible FF7's idea is just a coincedence to ToP, but the similarities are totally there. The fact that both cities have the same name (origin) just makes the connection that much more obvious.