I had a friend ask me "if you could run SD and have any roster you wanted (within reason) who would it be?" So you could make something 'worth watching'.
The numbers I picked are around half of legitimate performers under contract at all three shows.
Parameters (30 on roster) were 15 singles, 5 tag teams, and 7 women, 2 non-wwe, 1 GM
Singles: Styles, Rollins, Owens, Nakamura, Somoa Joe, Roode, Zayne, Bray Wyatt, Cesaro, Rusev, Neville, Corbin, O'Neil, Aries, Axel
Tag: Anderson + Gallows, American Alpha, Revival, Harper + Rowan, Vaudvillians
Women: Sasha, Becky, Asuka, Paige, Bayley, Emma, Lana
FA: Cody Rhodes, Sandow
GM: Shane McMahon
If you think about who all that would leave available for Raw, I think it's a fair list.
This is a roster, with actual pro wrestling booking, could hold mainstream fans of today, and the fans (entire demographic) of 10 years ago could be lured back. Just something to share. Ideally I would be able to add 5 more singles in the jobber tier.