AS an avid WWF(E) fan, it depends on what your defintion of biggest star is.
If were talking "made Vince alot of money" then the list goes
1. Hulk
1B. Austin
2. Rock
3. HBK
4. Cena
5. Warrior....mabey taker
If were talking "amazing to watch" then
1. HBK
2. Austin
3. Rock
4. Hulk
5. Taker
Honorable mention: Bret, Jericho, Eddy
If were talking pure "this guy was the complete package, can talk, work in the ring, and sell"
1. HBK
2. Bret
3. Austin
4. Jericho
5. NWO era Hogan
This generation, there are only a couple guys who can even approach that level, and alot of them are hampered by Cena being the only "top guy." Cena's servicable, but he is what he is.
Crownsy's current list of guys who I suspect could hang in the golden age/ attitude era, but will never get the chance to show how good they could be due to current product
1) CM Punk
2) Daniel Bryan
3) Cody rhodes
anddd... here comes the your crazy 4th guy
4) The miz. I know, i know "the real world guy?!?!?" but the last 2-3 years he has really upped his in ring work and the kid is gold on the mic. Not saying he would have been a star in the late 80's and 90's, but he would have carved out a spot on talking alone.