I remember not liking Ali much when I was younger due to her initial prejudice against Littlefoot's friends. However, since then, my opinion of her has improved. This was her character arc, after all--later on in the movie, she realized, "It takes all sorts." And even when she was prejudiced, they played it not in an obnoxious/snobbish way (i.e., Cera in the first movie) but as a misguided fear, the result of living a sheltered life among one type of dinosaur only. Despite this fear, she was willing to go straight to the rest of the Gang for help when Littlefoot was in trouble, and she warmed up to them from there.
Even though Littlefoot+Ali isn't a ship I was ever very excited about, they're cute together, and I think it's pretty safe to say Ali was intended to be Littlefoot's love interest. I mean, there was that whole montage of Littlefoot and Ali scenes at the end of the movie, and how many one-off characters have gotten that sort of montage? That's right, just one, and you guessed her.
