#4 Sable
She has technically been retired since 2004. She has done a good job at staying out of the spotlight, despite being married to the biggest star in the entire industry.
During her relatively short career, Sable was able to soak up a lot of great experience, during some of the sport's most popular eras. Starting back in the mid-90's, Sable actually made her debut at Wrestlemania 12 as the valet for "Hunter Hearst Helmsley." Of course, she would eventually go on to work with her former husband Marc Mero for an extensive amount of time before making her singles run and winning the WWF Women's Champion before finally calling it quits and retiring in 2004.
Since leaving the sport, Sable has been very vocal in support of her husband Brock Lesnar, regardless if it's been with WWE or MMA, she's certainly stuck by her Beast.
Wrestling doesn't necessarily need someone like Sable to make a full-time, permanent return. After-all, she will celebrate her 51st birthday just a few months after Wrestlemania.
However, fans would probably love to see Sable make an impromptu appearance at Wrestlemania 34, competing in the Women's Battle Royal. I'm not very hopeful that this one would become a reality, I just think she would provide that surprise moment that we often hunger for as members of the WWE Universe.