I would go lighter as I love the serenity of bedroom in light tones but that's a personal feeling. I also prefer a color that blends well with the wall color. I generally try to keep the continuity going in a bedroom. You really can go either way. Darker enhances the window and somewhat breaks up the room. I prefer not to break up the room. Just my opinion, I'm sure it will look lovely what ever you choose.

We are merely taking stabs at this without seeing photos. I would want the drapes close in color to the wall, but slightly darker rather than slightly lighter. My concern would be that the drapes wouldn't have enough presence in the room against the yellow walls.

You also need to take into consideration the comforter colors and make sure they don't clash with the ivory or gold, depending on which you choose.

I think I will buy and install rods first. Then, I will buy one panel of each color and go from there.