I am saying this as a person who buys only her ticket, so to me the expense is worth it. I have been to different Disney hard ticket parties and Halloween was BY FAR my favorite. The parade is FANTASTIC, and the atmosphere is really fun. At the time I was 27 (29 now) and I was a bit nervous to trick or treat as an adult despite it is encouraged...with a little encouragement from CMs, we had an absolute blast trick or treating, which I hadn't done in maybe 12 years or more!! Sitting in the hub grass eating a ton of candy and watching fireworks was honestly a Disney magical feeling! I would definitely vote for you to go if the tickets work into your budget. It was a really great experience and I am going again this year - in fact it was one of the bigger factors for me in deciding when to go again.
ETA: we weren't super big on waiting for characters so we did avoid those lines that seemed lengthy and focused more on candy and rides, and had a great time. Also, outside Haunted Mansion was an actress doing a super cute "ghost" skit and interacting with the crowd! It was so cool we let people go ahead of us in line just to watch.