IMO
>Gen 4>Gen 3 (OR/AS preferred)>Gen 2 (Original preferred)>Gen 5 (B/W 1 preferred)>Gen 1 (Original preferred)>Gen 7>Gen 6If you guy's haven't heard Gen 7's Trainer Battle theme, here is a spot on recreation
https://www.youtube.com/watch?v=ALSbf6_iFoEIt sounds really nice, but it doesn't have the intimidating flare of previous Trainer Battle themes which I find really appealing.