I would quilt the center by following the design in the picture. Outline the horses, outline the grass and sky and use green thread to add detail to the tree boughs. Outline stitch both of the frames and stitch some of the flowers and background in the outer frame. Once the center was quilted I would meander in the cream areas if that is what you are good at. The log cabin and other blocks could be SITD.
Don't think about how you will get the whole quilt through your machine. Concentrate on the foot square you have under the needle and puddle all the rest of the quilt on the table so there is no drag.