At that time of year you are unlikely to run into major crowds on any day. SW takes crowds pretty well anyway, because a lot of the action revolves around shows and larger animal exibits, if you do hit a busy day, just allow a little extra time to get seated at the shows. Kraken and JTA can get busy later in the day, so if you want thrill rides , it's best to do these early. The only other possible snag spot, can be Wild Arctic, just after a Shamu show clears out. You get thousands of guests coming out of Shamu stadium and the first thing they see is the queue for Wild Arctic. Try to avoid being just after a show finishes and you should have no problems.