You will likely have a longer wait for the monorail than the amount of time it takes to walk back to BLT...especially if you leave after the fireworks! Enjoy the Resort!!!
POR is a great resort! Their food court is one of the best on property! If you decide to become DVC members you will not be disappointed. We are members and purchased SSR in 2010.
Keep checking! We have done both. While the magic of the Castle is great...we really liked the breakfast at Akershus too! My daughter loved both experiences! Akershus seemed a little less stressful.