This Game is Overrated

[WildRaubtier]

Most of the FF VI cast though does have a relationship to the Empire.

Terra - Imperial Slave Doll/magic experiments.
Celes - Imperial General turned traiter
Edgar and Sabin - Their Kingdom is in a misleading treaty with the Empire, and they are consipiring with Rebel forces to oust the empires control.

Cyan - His entire kingdom, including wife and kids, were poisened and killed at the hands of Kefka during the war between the two countries.

Strago and Relm - Their introductary arc is there connection to the plot.

Locke - Member of the rebels, as well as the Imperials marching through his home caused his girlfriend to go all coma like.

Gau, Umaro, Mog, and Gogo are the only ones without any real connection to the empire of the cast.

So yeah, the majority of the FF VI cast is pretty invested in the fight against the empire.

You've missed the point entirely. Terra and Celes both have a fundamental relationship to the empire, and their personal stories are used to drive the plot forward. Edgar does as well, but it's wafer thin. Sabin, however, is literally the brother of another cast member who lives in the mountains. You can move him to a different game, making minor tweaks for context, and neither his story nor that of VI would change.

Locke, for example:
He wants to protect Aeris because he was unable to protect Rachel. Later, he finds the Phoenix materia but is unable to revive her.
He wants to protect Dagger because he was unable to protect Rachel. Later, he finds the phoenix pinion but is unable to revive her.
He wants to protect Yuna because he was unable to protect Rachel. Later, he finds the phoenix fayth but is unable to revive her.

Or Cyan:
His family is killed during the attack on Trabia Garden. He is soon given the chance to say goodbye properly at [VIII doesn't have a weird spiritual place, lets say the phantom forest is in Winhill now].
His family is killed during Sin's attack on Kilika. He is soon given the chance to say goodbye at the Farplane.

In each of these examples, the character's story is not diminished by being moved to a different setting, nor is the story of VI diminished by their absence. This is true for almost all of the cast of VI. The reason is because they lack that key personal reason why they hate the Empire. Locke could be antagonised just as easily by the Shinra, Galbadia, Alexandria and his motivations don't change at all.

Finally, this is a thread were we have basically started comparing one game to another. So it's perfectly valid to point out that all the games we are comparing have the same problem, as bringing up that problem in one specific game does nothing to advance the argument, as it does nothing to advance one side forward.

It's a thread about the quality of VI versus how people perceive it. Saying that a problem isn't a problem because it's a common problem doesn't actually support any suggestion that its not a problem. Compare to support, don't compare to show how something else is wrong, too.

Like I alluded to earlier, V has an excuse plot and it's perfectly aware of it.

But that's fine, it doesn't need one.

I think it needs one...but you're entitled to your opinion.

Games having more than an excuse plot is an entirely recent trend. Does Mario need a reason to jump on all these platforms? Let's just say he has to rescue the princess.