Everyone's experience is going to be different. There is no guarantee of who is going to be at Goofy's (or any character meal) on any given day.
I've been eating at Goofy's since 1992, so I think I can safely say that I've seen a wide variety of characters come and go over the years. In the old days, when Goofy's was the only character meal at DLR, there were lots of characters. They would come at us, fast and furious, to the point where we couldn't get bites of food. Some people like it that way - I, on the other hand, like a nice mix of a handful or characters
and I like to be able to eat my food!
When DLR began adding in more character meals years ago, fewer characters began appearing at Goofy's. I have no clue why DLR decided to handle things that way, given that they charge a lot of money for Goofy's.
Currently Minnie & Friends seems to have the most characters (but consistently mixed - even bordering on negative - reviews of the food). You may see anywhere from 8 - 14 characters at Minnie & Friends. Some folks say it is the best one out of all the meals. Other folks say it is too disorganized and chaotic!!
All of the character meals except for Minnie & Friends seem to average at about 5 characters, give or take a few on certain days. Goofy's generally has anywhere from 4-8 onsite at any given time (and I am counting the one at the entrance for the photo op), but basically that's considered premium dining because of the wide array of food items in the buffet. Ariel's is considered premium dining, too.
I can say that whenever my friends and I are at Goofy's, we see Goofy, of course. We
usually see Baloo, we
usually see Pluto, we
usually see Chip & Dale, and we
usually see a couple of Princesses (who can differ), so it's about 7 characters on most of our visits. Sometimes it may be 6 characters. Sometimes it's 5. I'm only stating what the norm has been for us in a long history of eating there, and, specifically, what the average has been in the last few years. We've also seen the Mad Hatter and Alice. We've seen Max. We've seen Aladdin and Prince Phillip. We've seen Captain Hook. We've seen the Genie. Others have seen Honest John and Gideon. Others have seen Minnie. Some have seen the Fairy Godmother. (In the old, old days [pre-Critter Breakfast and pre-Minnie & Friends], we used to see Rafiki, Meeko & Timon, Jafar, Tigger, Roger Rabbit, etc.)
So I think, as Sherri said, that if the criteria is seeing the most characters, Minnie & Friends is the best bet. At any of the other meals, you don't really know if you will see 3, 4, 5 or 6 characters. And if meeting Princesses is the most important thing, then Ariel's is the guarantee for that (though it will still only be about 5 Princesses). I don't think there is any reason for you to try Goofy's again if you didn't really like it too much the first time.
