Our family liked BB better. Better slides, more variety for the kids. dd8 loved the Ski Patrol Training Camp, while Tike's Peak was great for dd2.
I believe there was only one kid's area at TL (Ketchakiddie Creek). My 2yo didn't enjoy Ketchakiddie Creek nearly as much, as it was too full of bigger kids spraying everyone with the water sprayers, running and jumping onto the (tiny!) slides in front of the little kids, etc. At BB, Tike's Peak was little kids only, so it was a lot calmer and better for those little ones, while the big kids were at Ski Patrol.
The family raft ride is way better at BB. The one at TL was so short, it was a joke, and not worth the wait in line (in our family's opinion). BB also has a wave pool, but it's different and just depends on what your family likes. TL's sends out one humongous wave every so often. BB's waves are more constant, but smaller. dd8 likes TL's better, but the rest of us like BB's better. TL also has Crush N Gusher, which is a blast, and since we don't have a "roller coaster" type slide at our water park near home, it was worth a trip to TL just for that!
Both parks are fun, though, you'll enjoy whichever one is open during your visit. Have fun!