Hmm, I agree that the hangar scene needs to have something juicy, and it seems pretty “duh” for Kylo to tell her Palpatine wanted to squash any potentially powerful Force user.
Tangential: Would it make sense to change Palpatine’s line at the start to “Find the girl,” and have Kylo Ren apparently lie to Rey that he wants her dead?
If Palpatine is then portrayed as wanting to bring the two together, it seems even dumber for him to be surprised about the Force dyad fountain of youth. (Well, not youth, but of being alive and having all your fingers and pupils and stuff.)
Palpatine’s surprise about the dyad could be cut, setting it up in the opening and replacing it with “and now, your coming together will be your undoing.” or “stand together, die together” springing the trap immediately, his talk about “the power of 2 will restore the 1 true emperor” could be VO as he sucks the life out of Rey and Ben.