Aloha,
I just got back from our first adult's only vacation to WDW and UO. UO was our favorite before this trip and after experiencing FOTL it became even more special.
On our two previous trips to UO/WDW we took our grandsons. And they too love Universal best. Can't beat Seuss Landing and Barney with a 3 year old! I guess it depends on your family.
When I was young (a very looonnng time ago) we had Mickey Mouse Club on tv and really knew the Disney characters. But now my DGS only know Mickey because adults have shown them his picture and identified him. They do know the characters in the movies like Toy Story etc, but not Donald, Mickey, etc. But my DGS do know the Dr. Seuss charaters and Curious George because we regularly read the stories and have the videos. And they knew and loved Barney when young!

But they know Woody Woodpecker and Popeye the same way they know Mickey, because adults have told them about them.
While characters may be family preference, FOTL is terrific for small kids. The only sad parts to our vacations with DGS happened when they wanted to ride something that had a long line. We waited forever to drive cars at autotopia and never saw the new Pooh ride because the lines never got short enough.

Little kids have a hard time waiting especially when it is hot. During our "childless" visit, we both realized that a trip with FOTL with kids would be wonderful. Also, the fact that the hotels are so close, we could have taken the kids back to the hotel for naps or a swim in a matter of minutes. WDW is getting too big to do that easily.