I NEVER EVER heard of GOT as a bad game. (Bad art yes. A hardware flaw on Premium/ LE did hurt the machine also.)
I only now the situation here, but you can nearly find no used GOT Pros, because people seem to like and stick to them.

Way easier to get a used GOTG.

GOTG started with pretty unfinished code, so that's a bad rep that may still cling to it, altough code has long been overhauled.
Personally I think altough pretty, GOTG is kinda blend.
I mean: Yeah there's Groot and Rocket Racoon and stuff but why the heck do I shoot them?
There's a reason the big Toy in Star Trek is the Vengeance and in GoT it's a Dragon, because you 'shoot the enemy'.
And the Enemy shoots back!
But why does Rocket Racoon shoot at me and why does Groot swallow my Balls and throw them back up?
Does that relate to anything in the movie?
Blend slapping of a license onto that game.

I forgot to mention that info in my post and modes is a good point.

Watched 5 Minutes of the animated GotG series on TV and saw Rocket Racoon in Marvel vs. Capcom for Xbox360.
Have not seen any moving pictures of GoT despite the Pinball DMD and didn't read the books.
So, absolutely no relation to these licenses, BUT...

...starting GoT, selecting a House and defeat all others to become the head honcho is an easy to understand goal and interresting way to open the game.
(Kind of like an adult Medival Madness.)

In GotG you... select some 'stuff'?

The voice acting is ok for me since I dunno the original voices in the first place.
But even in cases when I do, I mostly do not mind when they're 'sound-alikes' and not completely different.
(The guy that voices Johnny Mnemonic in the game does a good job in my opinion.)

I don't talk about the rules. I talk about the goal. The goal is to defeat everyone. That's easy to understand and there's Stuff to shoot at.

The goal in GotG... I have no clue.
And for somevreason I shoot the good guys.

After that the 'initial' rules are easy. Shoot blinky things and don't loose the ball to complete modes.

Rest comes later.