Help with coloring techniques and background color ideas

[fluid jay]

Light soft blue for the darkest shadows has made wonders for me! It makes everything, specially the skin, pop out a lot more.
As for the background I'd say to make a stained glass window as of those in the churches?
The art is beautiful btw!

[cunning wraith]

First, i love how neat your line art and the hands omg thats so good.

For backgroumd? If you wand some religious aura maybe choose blue with gradient but if you want contrast, try yellow