TBH I cant help but wonder if this is the real reason the Daleks needed the Doctor, the Daleks in the Asylum were not that active, what actually scared the Daleks, was the one Dalek, who wasnt acting like a Dalek should, and could seemingly control the other Daleks around it. Im betting the Daleks think that only the Doctor could get past her defences, earn her trust etcIn the end, she turned out to be a genius girl who got turned into a Dalek against her will and became so delusional about her predicament that she entered a dissociative fugue state. I think that qualifies as "a bit more bizarre" than "a regular old Dalek".
True, but I was talking more about her physical appearance. Obviously it becomes something special the more we learn about it, but my initial impression was still "oh, it's just a regular Dalek who's been doing all this. Ho hum."
When the Doctor thinks she is just a girl trapped in the Doctor Asylum he will do all he can to save her and earn her trust, then when he finds out she is a Dalek, they know his hate for them, will make him force her to see what she has become.