First of all nice concept
As you know Artwork is very subjective as you can tell from my stuff I do and is only my opinion
However you might want to try a few things which may work or not
separate the white banding, scale up abit and solidify to give depth,
Add a slight bevel to the g
And try your colors in a color wheel
Lighting with a hdri not just scene lighting
Try the camera in orthographic not just perspective
set your scene to be in high contrast or very high contrast
The list can go on
I find modeling is the easy bit, texturing and lighting is always the hard part
I hope that gives you a few ideas to play with
I've got a HDRI for that scene. I'm using spot lights for the coloured one to get the colours in the scene tho. The HDRI I'm using is the "Small studio"-HDRI from HDRI-heaven.
Oohhhh, that makes sense for a wallpaper.... now I feel a bit silly xD - it seems so obvious after the fact LOL
Hmm, I wanted a not a very strong contrast since the scene should be "mild" to qualify as background.
Yep, I'm pretty sure it does. Especially since this is just an out of the blue quick thing to test my computer but I started to like it and wanted to refine it.
Although I love playing around with all those shader nodes. Sure this one is just a simply glass with some BSDFs but I like nodes and what they actually can do. It is mindblowing to me everytime.
I'll come back after trying out your suggestions and show you what I can come up with.