I would watch them both from the park and not from Pirates and Pals. We did Pirates and Pals 2 years ago and wasn't impressed.., the pirate part was OK...nothing great. The snacks were cereal bars. and packaged cookies..again not so great...you had to wait online for picture with Smee & Hook (you can do that in park) and I didn't like watching the fireworls from out on the bay. They piped in the music and all, but I think something was really lacking by not seeing the entire castle and being up close and personal as you are in the park. If you can, I think Wishes dessert party is a mcuh better way (and value) to watch MK fireworks.
The Illuminations Cruise is a different story as you are right on the water with the fireworks seeing them up close and personal. With Wishes I think a large part of the magic is seeing the castle all lit up and sharing the ooos and ahhs with the rest of the crowd, you lose that with Pirates and Pals.
Plus you get assigned seats on pirates and pals and one side of the boat is a a bit futher from watching then another...