I would go with the deeper red also. If you have enough options and like the scrappy look, use different red fabrics for the red hearth. On the other hand, that center square is usually so small having it consistent through out the quilt can sooth the multiple colors you are using in your logs. In my opinion, black, yellow or orange would pop and you would lose the soft warmth of the hearth. In the end, it is all about what you want to achieve and what pleases your eye.