The "is it worth it question" is almost impossible to answer. It is incredibly subjective and everyone's situation is different. I try to think of it as what other entertainment experiences I could get for around the same money and decide from there. So at just over $50 per person, it is less than half the price of a day in the parks, as an example. Or equivalent to the admission at a local admission park, or the cost of going to a dinner show at WDW, etc...
As for the Star Wars Dessert party itself, we really enjoy it and have our 3rd one booked for our upcoming trip. There are no character meet & greets, but you will have Storm Troopers walking around. You are inside Launch Bay so you have easy access to the character meets in there, but you get no special access to them, you will have to wait in line. The food at the party is good. There are a few savory options and lots of great sweets along with plenty of different beverage options (alcoholic or not). The one big disadvantage is there is no seating (with the exception of one bench near the stairs to exit the party area). There are tables to stand at, so you don't have to try balancing food and drinks, but it can be rough on your feet especially after a long day in the park.
For me one of the biggest advantages is a reserved viewing spot for the show, which they lead you to at the end of the party.
So I guess my answer is, if it is in your budget then yes I think it is a worthwhile experience.