Absolutely! If you can see them now, grab them.
We did this last December, and are realatively seasoned veterans, and loved the one thing that is hard to find during parades and fireworks...SPACE! Plenty of room to spread out, lay down (in the grass), etc. For the electrical parade, loved having the castle in the background (we were there in December, so lighted), and although you are slightly to the side for the pre-firework shows, it is fun to have tink fly right over and have the best perspective for the fireworks...which I often don't stop touring to watch.
It is a perfect use of FP+ for those who have been there/done that at the parks. Pack a poncho to lay down on in the grass (rose garden), a snack to share, and enjoy!
We arrived maybe 30-45 minutes before our entrance time for EP, and were sitting on the curb facing the castle. One row of adults standing behind us. My inlaws were able too find a bench to sit on in the same roped off area.
We are not usually parade/fireworks people, and honestly, using the FP+ is probably the only way I will view them in the future.