This is great! What a wonderfully presented set of parallels. It brings it home to me how much more angsty the present day is than so much of the Old Haixing interlude--the dark tension of modern!Shen Wei's knowledge that he's heading toward a tragedy, and if he's lucky might be able to prevent it by being the only one who dies, versus the sense of hope for the Alliance's victory and happy coexistence under Ma Gui and Fu You?
Um, except for the cake. That is also an excellent parallel--VERY SUGGESTIVE sweet-eating--except that, as I pointed out before, Zhao Yunlan knows exactly what he's doing and little!Shen Wei (probably) doesn't.
For the record, I don't think Li Qian is immortal--I think her grandmother dealt with that issue during her well-timed posthumous appearance. I don't think she would want to be. (Maybe a bit longer-lived and healthier than average, getting back what she gave her grandmother with a bonus...).