This is beautiful. Your use of color and value with the shadowing behind the cross radiating to lighter shades is quite inspiring. If your border is not wavy now it should be fine once the quilt is completed.
For binding, I am a bit of a traditionalist and prefer the look of a separate binding that is machine stitched to the front then folded to the back and hand stitched down. To me it just finishes things off nicely and neatly. You have so much work and love invested in this piece now, why cut corners at the last stage?