So i recently came across this video by extra credits 

It talks about how the game music industry evolved and such but it got me thinking

Would you rather have game music which is memorable or game music which is forgettable but does it's job exceptionally well when it comes to creating mood and such

Obviously there's got to be a balance between the two. I always believe that at least a few tracks should be memorable within the game. Having every track trying to out-do the last one is the wrong idea. Some songs only need to have a simple string/pad while others require full orchestration.

I'd say, it depends.

Let's say, you're in a dangerous cave. You certainly want to capture that sense of anxiety in your score. Maybe some dark atmospheric pad with a few awkward noises. You don't want your players to whistle along here.

On the other hand, when portraiting a strong and important character, faction or place, you want to use a strong, recognizable theme. For example, if in the dungeon from above, you start fiddling in the theme of the big bad boss, players will subconsciously sense what's coming without knowingly recognizing the theme, necessarily.

Of course, it all depends on each individual game. So, if you, say, have a lounge before your online matches, you probably want a theme that makes players feel comfortable and ready for a fight while not poking their nerves too much if gets repetitive.

Your question doesn't have a simple either/or answer. So I hope, I was able to help, anyway.

I agree with ptietz. It really depends on the purpose. A theme is a theme. Background ambience/music/fx should serve the mood/vibe foremost. But I'm sure it would work the other way around for some games also.