Hello guys! What i need is help!Well you see i vectored Arc,but i dont know what to put in the background...I came up with this but it's to empty(P.S. i puted my copyright sing in case it wont be ripped)

i think it needs lighting
id use the soft brush tool 300-500 and just put one point [one huge point ] of white at the top, where the moon is and then change the blending mode to something like overlay... just try to experiment with other ones, and then choose the best
then id paint the night city as a perspective, not detailed, just lights, red, yellow, blue...
thats all i have hope it helps at least a little bit

the sky seems empty so add some clouds
& you can add two vases with flowers on both sides also you can add petals to make it look more beautiful
the vector is gorgeous
well Im not a very helpful person sorry~

what about this one?
The biggest problem is that something happened and i cant correct anything anymore...
2 version

also without moon or?
3d version

I'm having the same problem with a wall right now I'm done except for the sky, which is empty. It's killing me Since I'm supposed to submit it today.
Anyways I like all the ideas already mentioned. Lighting and clouds would help. And good luck.

need more into the wallie i think you could took off the moon away? and put some clouds on it?
anyway, i like the cities under there :3

Neat vector job!
I like the colors so far, but there's something bohering me...
Ahh...yeah, the moon: I think that it's waaaaay too real :S Maybe some painting would do the trick.

For the background maybe a starfield.
And, as everyone has said, the lighting is a good idea.
Hope it helps.

i uploaded wall

i think u should keep the moon and stars - maybe a few clouds as well?