Ahhh, the room exists and you changed the lighting. Good work!
Look at the first post photos here: new Layout progress
I use Sherwin Williams Tibetan Sky,#7134. it's my eye's match of the horizon just above tree line on a perfectly clear sunny day.
The green that I chose is Sherwin Williams Generator Green #4070.
Use the primer from the same manufacturer of paint that you choose to use everywhere. Then, the colors.
I like an eggshell base. Doesn't hold dust as much and can be wiped with a damp sponge or cloth.
That's my 2¢.