You'll want something on the darker side in complimentary contrast to your light fireplace and walls, but not as dark as your hardwood. I think one of these four would work well for the entire space. Try getting a larger sample of each one of these to really get an idea of how it would look under your lighting.

Here is a close up of the colors on the bottom 3 rows. So that you can see their names. These are the colors we are trying to choose between on the sample board. We do have 2 little kids but no pets so we are ok with a lighter beige as long as it won't be too hard to keep clean

Try those two dark samples and two light samples you like then. If you go with a light carpet, consider adding furniture that is a bit darker, you'll want contrast somewhere or else the space will come off as a bleak monotone.

Yeah we planned on getting dark grey couches once the carpet is installed

Sounds great, if you wanted you could even add a coffee table or small lamp tables that match the fire place mantle shelf or the hardwood floors for blending.