I honestly don't have a favorite between TL,BB and even the newest waterpark in the area Aquatica,they each have pros and cons.
BB: Has very good slides overall,thrill slides,tube slides and a huge family raft ride.Theme is unique but too much white fake snow can make the sun hitting it bothersome on the eyes.Lazy river is good but the cold water hitting you inside the caves is annoying.Wave pool is relatively small and boring.I dislike the layout of the park with all the slides up the mountain so you have to keep going up the same 2-3 staircases which gets boring.There's a couple of slides that also allow you to take a chairlift up but there could be a wait.
TL: Nice relaxing tropical theme,some slides such as the family raft slide are way below par,although the Crush n Gusher water coaster is great and one of the best of the three parks.The lazy river is great as is the huge wave pool which has the huge waves that knock you down as well as the regular bobbing waves at certain times,be careful when the big wave knocks you down as the floor is very rough and likely to scrape your knees.The shark reef is unique and fun to try but remember the water is very cold.
Aquatica: Newest waterpark in the Orlando area,very clean and has the best dining and shopping options of the three parks.It has two twin wave pools with one having slightly bigger waves.Slides are good but not amazing,the park has a smaller feel than the other two with a New Zealand theme,less trees than the Disney parks but more palm trees and color everywhere.The dolphin plunge slide that has a clear tube and goes through the commersons dolphins pool is cool to see as a spectator but don't expect to see the dolphins as you slide down.It has two lazy rivers one being a smaller traditional lazy river that you get the tube at the same location as where you get the tube to their bowl slides which can get confusing for certain guests.The other lazy river is the coolest thing at the park as it is a fast lazy river that you only wear a vest and follow a fast current all along the river,I could spend an hour or two in there if you let me.
About 10 years ago before Aquatica opened I was certain BB was my favorite over TL,now TL has grown on me and Aquatica is right there alongside them,and like I said earlier all three are good and totally worth it.