It's hard to nominate anyone from ECW - the promotion was only around a few yrs, how can you say the body of work someone did for a short time in one decade was Hall Of Fame Worthy ? No one should be in the HOF simply based on their ECW careers, although the work that wrestlers who achieved greater long term success in one of the major promotions should have their ECW days counted towards their worthiness.
Also, WCW should be alligned with the NWA. For all intents and purposes they were the same promotion, only changing names about a year after TeD Turner bought the company from the Crockett family. The only thing that changed was WCW did not cross promote with smaller regional based promotions as much as they did under the NWA banner. However, most of those promotions had gone under by the early 90's and the top wrestlers absorbed by WCW, WWF, or Japan.
There are numerous wrestlers who deserve HOF status...Since I am unfamilair with everyone in the WWE version of the HOF some of these maybe duplicates (I apologise in advance)...
Road Warriors - Dominated the AWA, NWA, and Japan, plus had a very successful run in the WWF in the early 90's. It's already been mentioned how many titles they won, they also particiapated in some of the most popular fueds of the 1980's against the likes of The Horsemen and The Midnight Express back when tag team wrestling was promoted as heavily as singles wrestling.
Verne Gagne - The "father of modern wrestling, Gagne trained many of the top stars in the industry including Ken Patera and Ric Flair. He successfully ran the AWA for two decades, giving major pushes to future WWF stars like Hulk Hogan, Shawn Michaels, and Scott "Razor Ramoan" Hall. His 9 world titles were a record (broken by Ric Flair in 1993)[/I].
Nick Bockwinkle - One of the great heels of the 70's, Bockwinkle was the prototypical cocky bad guy, mostly in the AWA but he appeared in the other major promotions as well. In the 1980's, he became the "elder stateman" of pro wrestling trying to save the AWA from the evil clutches of hated Larry Zybysco, while adding multiple runs as World Champion to his credit. A solid brawler but very good ring technician, his matches late in his career against Curt Henning were some of the best in wrestling in 1987 (their near 60 minute long re-match for the AWA Title was one of Henning's all time best televised matches). Stayed active with on air roles in WCW into 1995 even though he essentially retired from regular in ring activity by 1988.
Randy Savage - The Macho Man, next to Hulk Hogan, was the biggest star of the 1980's WWF. Unlike Hogan, Savage mostly played a villainous woman abusing heel, although he did have a solid run as a fan favorite while Hogan was off the scene in 1988 (coinciding with his first of two WWF title runs).
A far better in ring performer than most of the WWF roster at that time, Savage deserves credit for carrying Hogan to one of his all time best performances at WrestleMania V, as well as his retirement match against the Ultimate Warrior one year later (it took a lot to pull a good match out of Warrior). When matched up with other good performers his matches were typically excellent (see WrestleMania 3 vs Ricky Steamboat or WM 8 vs Ric Flair). After his WWF run ended in the early 90's. Savage went to WCW and continued to be one of the shows top stars, reviving his WWF feud with Flair and playing an integral part of both the return of Lex Luger and the NWO story line. Multiple (although short) WCW title runs followed. Savage left full time wrestling in 1999 and has been seen little since. Add the fact that he was one of the top stars in the Mid South region before he joined WWF and you have a twenty year career of mostly main event status feuding with and wrestling against the biggest names in the industry.
Bruno Sammartino - Simply put, the entire WWF was built around this guy as his seven year long title run would show. The WWF never would have gained the popularity it did in the Northeast US if not for Sammartino. Two reigns as champion spanning a total of nine plus years and the fact he carried the promotion (very successfully) for 15 years and this guy is a shoe in.