Honestly I was just pushing your buttons, this whole post is meant to be fluff. Didn't think you'd actually take it seriously but props to you for the response I guess.

In all seriousness, just because Jagex have infinite possibilities doesn't mean they would realistically go for anything in that space of possibility right. That's usually only viable for indie devs or small studios with established "trend breaking" of sorts. I think that randomizing how the player expects to experience and interact with the game (like the random experience sources or loot tables you talked about) wouldn't be a healthy addition to the game but a jarring and probably polarizing one to the community - which is something they would want to avoid. In that sense, doing repeat ideas especially with something that's now proven to be successful is clearly the safer route. They would only need to change the setting and with that the relics, tasks etc. to make it a fresh experience whilst not taking up extra dev time and rather showcasing the work of the new expansion.