The whole point of this ride should be its height. It's the tallest coaster in the UK, that's its USP and no theme or story will add to that in a meaningful way.
I'd be all for the front car having a cool style (a la Untamed at Walibi, for example), and some stylising in the area (like Fury 325). But beyond that, I don't think theming is necessary.
What is important though is, regardless of theming, the area is well presented and bright. I don't think another dark, dreary feel is needed.