the Tardis's active dislike of Clara is another plot point that seemed, at the time, like it should be significant but ultimately goes nowhere.

Moffat has hinted that this will be addressed before Clara/Jenna leaves. It has been dropped in recent years, though, which makes one wonder how it will be reintroduced. I always assumed that the TARDIS picked up on her 'impossible girl' status and disliked her for it, similar to the Doctor not being able to stand Jack's immortality.