If I recall from reading past WCB events, usually most of the roller coaster riding is done at morning or evening ERT.
Get there early and get your rides in, when the park opens go to breakfast. During park operating hours TPR has plenty of activities to do like scavenger hunts, Q&A sessions, backstage tours, lunch, etc. while all the regular guests are dealing with crowds and waiting in lines.
Then once the night comes, the crowds thin out, night ERT begins and you get to go on anything you want that you didn't go on in the morning!