Hard to say. I have missed a dew years from the 1990s through to today but there are patterns in Wrestling i how they do pushes and things like monster heels and what gimmicks work (and are popular). For example you often have.
1. Mr America (Hogan/Cena)
2. Mr Monster Heel (Andre/Gonzalez/Khali/Brock)
3. Mr sneaky (mid sized heel with a mouth, that is The Miz right now, HBK at certain times)
And there is probably other archetypes. How effective they are depends on the performer.
Lesnars gimmick is going to get old fast. Its kind of boring watching him suplex city people and he lacks the charisma of other heels WWE has had over the years. Orton has been around since 2002 and in wrestling your shelf life is more or less 5-10 years with a few exceptions like HBK/Hogan/Flair.
They need someone new, Reigns did not work out so well and they have done things like have Foley hand over his bat to Dean Ambrose. The Lunatic Fringe is not really that different conceptually to Mankind lol.
Will WWE screw it up is the thing. Lesnar has beaten the old guard (Undertaker, Cena, Orton) and if they bring back Goldberg I expect him to beat Goldberg as well. The person who beats him in effect has indirectly beaten the AE/RA erastars and will get a major push by the company.
This is just IMHO but a heel turn by Reigns and a face turn by Stiles I expect in the near future (within a year). Reigns started to get cheered when he acted like a tweener with Rusev and Lana.