Overall, I think the main featured star of the company was Shane Douglas. In addition to what has already been said about him here, I'd add that he was almost always mixed up in the main event scene throughout his entire time in ECW, in both the pre-PPV era and the first two years of the PPV era. Even in 1998 when he was hurting and not able to work as much, keeping the title on him didn't really seem wrong because he was a huge star in the company. And when he wasn't involved in the world title picture, he was still a part of one of the most memorable moments in ECW with Pitbull 1's broken neck and all the promos and segments that went a long with that issue. Shane was probably the most hated man in the company at the time, even as the World Champion Raven was busy stealing the Sandman's family away from him in a super-intense angle. Being paired up with the #1 hardcore woman, Francine, also greatly enhanced his star power, as well as leading the main Triple Threat heel faction for years. And as he was about to leave the company in early 1999, they did the storyline with Shane passing his boots on to the "next Franchise" of ECW, and this helped launch Justin Credible into the main event scene. And Credible was probably the main featured star of the company over the last two years.
So I think Shane Douglas was the most prominently featured star in the history of the company. But if you want to know who the Hogan of the company was in terms of crowd reaction and booking, it probably is a battle between RVD, Sandman, and Taz.
Taz rarely ever lost a match from late 1995 through August 1999. For four years he was an unstoppable force, and once he split with Alfonso after Barely Legal his crowd reactions were deafening. He would often no-sell big moves like suplexes and 911 chokeslams just like Hogan would. Taz could never be pinned unless you did something out of this world, like put him through the damn ring. Similarly, Hogan rarely ever lost a match clean.
Sandman obviously had the 10-minute long entrances that made him seem like the biggest star of the company. And he probably was the biggest star in ECW in 1995 and 1996. He always got the massive crowd reactions no matter what from that point on. And though he was a main event player in the pre-PPV era of ECW, he lost tons of matches after that. And he was not nearly the unstoppable force that Taz was in the ring. But you could still argue that nobody got better crowd reactions than Sandman.
RVD had the amazing crowd reactions and he also won the vast majority of his matches. And he made that TV belt feel more important than the world title at times. But I would guess that Taz was the bigger star in 1998 and most of 1999 and was pushed as a more unstoppable force. RVD woyld have a 20-minute mtach with a guy like Gudio and sell like hell for him, whereas Taz would just destroy Guido in seconds and no-sell some of his moves at some point. RVD was not nearly as invincible as Taz was, even though RVD almost always won his matches. But RVD's popularity was ridiuclous, and RVD likely would have gone on to be the biggest star in the history of the company if the company survived. But RVD didn't appear much in later 2000 as money issues popped up and he rarely main evented the big shows. I think he was on the brink of taking over as that central figure of the show after Mike Awesome departed, but a broken leg slowed him down some and then unfortunately ECW went south soon after. RVD also wasn't around for the earliest years of ECW, so that hurts him a little in the comparison between Taz and Sandman.
Between those three guys, I'd say Taz's presence as the unbeatable asskicking no-selling crowd favorite had the most in common with Hogan's push in the 80's.
You can't really go wrong no matter who you pick among the mainstay players, even if it is guys I haven't mentioned like Dreamer or Sabu. That was another one of the great things about ECW - there wasn't necessarily one guy that the company was dependent on as the main attraction the way that WWE has depended on Cena over the last 6 years. For the most part, ECW made many guys seem like legit top-end talent.