Genuinely? None. Cora reminds me of the character on Eastenders, I don't personally like Delilah or Harper, and Hallie sounds "made up" to me even if it isn't and I'm not keen on it anyway.
And isn't Hallie one of the names Sue Radford has recently chosen - not that that is a bad thing but it's an unusual-ish name and people might think of that straight away. Delilah's story in the Bible is relevant here (betrayed Samson). And the song Deliliah (some people consider that song a bit dodgy). Then there's Harper Beckham, so another high-profile "celeb name" perhaps? Think about whether any of these connections or connotations would bother you, or cause undue bother to your child.
None of them are really truly awful names (to me) though. If pushed, Harper is the best of the 4 I'd say.
However, it's very dependent on your surname, some of these names might sound great with your surname and thus make a nice sounding name overall. And the opposite.
IMO, be very careful with unfortunate initials and how the name sounds, with and without the middle name(s). Also it's best not to have sounds at the end of one name that run into the next. These things are more important than which of these all-okay names you choose.
(Nothing against "made up" names either, by the way, if that's what you are after, and not sure if Hallie actually is one. But if I'm thinking it, others also might.)
Apols for repetition, didn't RTFT.