First off, if some of your family is wanting to do the thrill rides, you may want to do these first. I haven't been there since they added Manta; but I remember waiting in line for about 45 minutes for Journey to Atlantis & Kraken. I asked a similar question about the rides, and most responses I got were; if you hit the rides first thing, your wait time won't be as long and you can probably do all of them done in the first hour. I would start with Manta, hop on over to JtA and then hit Kraken.
It's really hard to determine a plan at this time as the show times are not yet posted. This will have a big effect on how you make your plans for the day.
This is how we're hoping to do SW on our next trip:
Manta
JtA
Blue Horizons (Dolphin Show)
Dolphin Cove
Kraken
Penguin Encounter
Clyde and Seamore (Sea Lion Show)
Lunch
A'lure - Call of the Ocean
Wild Arctic
Believe (Shamu)
Reflections (If it's showing).
If you look at the map, we'll be going left to right. This will vary according to the show times for: Blue Horizons, C & S, A'lure and Believe. There are only so many shows during the day, so your visit needs to be planned around these shows (if you're planning on seeing any or all of them). We followed this plan last time and it worked great for us. We were able to see everything in one day. The addition for us this time will be Manta & A'lure. We had time to kill last time, so shouldn't be a problem.
You can keep checking their website to get show times (
http://www.seaworld.com/ParkHours.aspx?locID=1). This will help you get a better idea. HTP