Upon further consideration, most unicorn abilities are spell-like and tied to their horns, so I think I'm leaning toward the dismissal option.
Giving them planar turning inadvertently ties them to a deity, which doesn't feel quite right.
Cleon said:Don't see how planar turning ties them into a deity any more than them being able to turn undead does.
A racial penalty on the opposite alignment? We could do that, though it would be unusual. Then again, it shouldn't be easy. Sure, I'm ok with that.
Turn Conjured Spirits looks fine, but let's combine it with the turn undead. What effective level should it have for turning? The original is at 11, compared to 4HD, which might be a bit high. Something like HD +2? Determines both turning ability and times/day?