Thanks for your efforts. You have been persevering with these colours since the begining. Can I suggest you use colour in the text and focus more on a polished concrete look in the logo. I think there is some potential in a slab coming out of the G but you will have to try a few things out. The G should be an ultra modern minimalist shape. Polished concrete is used in a lot of high end architect designed homes here and can be used in kitchens, bathrooms and outdoor rooms.
#76, #77, #78 ..I made letters G and C reversed as a background of slab and #76, I created the shadow of the letters G and C in top of slab. how about this ...