Need paper mason help

The color is probably what is bothering you. You'll probably need burnt sienna if you haven't already used it. You'll want to let everything thoroughly dry and consider a matte seal coat before proceeding. Then add some color layers in washes. I suggest you set up a practice piece for sampling the colors, rather than directly on the house. Good luck, and don't worry. You can get to a satisfactory color with layering. Just take your time.

I've never sponged it on so can't help you there. But I do know that with painting, I usually do thin washes of a variety of colors to create the depth of color. You can use chalks as well. I think your grout lines being as white as they are, are probably what is bothering you. Maybe try darkening the grout lines with a tiny brush and some thin gray or tan color (or whatever you envision the grout color to be). Let it dry and then go back over your bricks with some variations of colors.

I agree with what Debora and Selkie say... I'd go over various bricks with washes of different colors... burnt sienna, a chocolate brown....

try on a practice piece, but you could probably even go over the whole thing once you have touches of other colors with the grey stain you used at first, then blot some of the grey back up with a paper towel...

you could even dry brush a little ecru over some of the bricks

I knew you guys would have a solution, the washes have begun and i'm lightening as I go