Oh wow, lots of replies.
Yes, the game is Titan Exodus 2. It's my own personal "Duke Nukem Forever", and it has had countless iterations, of engines, of graphics. 2 demos of it have been released in its time, as well as a beta. But they're all old and horrible now, haha.
Titan Exodus, Titan Omega Revelations (and TOR 1.5), Titan Genesis (abandonware, unfortunately) are all creations of James Whitehead of satansam.co.uk, a good friend of mine. And in times past, he did like to trace a bit, oh well got him where he is today, I suppose...
The waterfalls are probably the oldest things in the screenshot besides the backdrop, so I'll have a go at tidying them up and making them look a little more dynamic.
I'll have a go at tweaking the contrast of the sprites and the backgrounds to improve the readability. In motion I don't think it's as bad, but in static screenshots they definitely melt in.
As for fading the rocks out as it gets away from their surface, thats actually how the rocks used to look (very similar to the purple rocks in the screenshot of TOR). But they looked really flat and crude, so I redid them to their current form. EDIT: actually I think I have some ideas which might help this.
Thanks for the feedback