Of course Rey is a hall of famer. No question. From a championship perspective, in addition to the world titles and Royal Rumble win you mentioned, he's held the Cruiserweight championship 8 times including WCW and WWE, the Intercontinental championship twice, the WWE tag team titles four times with four separate partners, the WCW tag titles 3 times with 3 separate partners, and the WCW Cruiserweight tag titles once. Aside from that though he's been putting on great matches in WCW/WWE since 1996 and has carried countless wrestlers to good matches. Guys like Mysterio, Jericho, Benoit, and Malenko made WCW Nitro watchable by putting on midcard bouts that totally outshone the shoddy main event matches between over-the-hill has beens like Hulk Hogan, Kevin Nash, Roddy Piper, etc. Factor in his massive popularity over the last several years, and I can't fathom how any could consider him not worthy of being a hall of famer. Of course the WWE hall of fame is a bit of a joke, but if it was as legitimate as it should be, he'd still be a shoe-in.