Thank you for the useful information & insight.
The track should not be repetitive. Someone is going to play my game for several hours (hopefully), the track must be varied enough and long enough that they're not switching off the music after 30 seconds. I tend to take two or three tracks and blend them because I seldom find this in albums.
In regards to your additional comments about combining multiple tracks together to loop. Is there a specific amount of minutes or time that you're looking for when combining those tracks so the player doesn't get bored? I agree that it's important that the player not get irritated and head for the settings to mute the music.
My personal preference is for happy, melodic tracks and the track is more important to me than the person writing the track (i.e. I will buy / download from anyone who has the type of track I like.)
Understandable, serving your game and the feeling you're trying to convey is far more important than who the track comes from.
Once again thank you