It should be fine. Remember to schlep the diapers AND a pad to change them on. Potty-trained? Be prepared for FREQUENT trips between rides!
We took DD at 22 months the first time and 26 months the second time. Each time was a different experience. She was nervous the first time on some rides we thought she's love (The Many Adventures of Winnie the Pooh) but just a few months later, we were riding Dumbo three times in a row (well, Daddy was. It made me sick). Also at that age, DD didn't want everything she saw. We told her to give all the stuffed animals she picked up a hug, then to put them back with its friends so it didn't get lonely. Worked every time.
Also, we opted for character buffets. DD REALLY liked Crystal Palace and attached herself to Pooh like velcro. We had to pull her off him. Even the CMs were laughing. Also at that age, they get to eat at the buffets for free, and it ended up being a good deal for us.
Good luck!