I imagine it depends partly on how long the objects been feeding off of magic. Although, in case of portraits, it seems to me that the painter captures some sort of essence of the person, the way they perceive it of course, which is why they are never the person they used to be. Clearly they are better than the animate pictures on the newspapers if you put them on a sentience scale of sorts, but, not by a large margin. At least how I understand them. Piertotum Locomotor is a very cool spell indeed!
Having said that, my favourite has to be Reparo like many people with glasses, and I really hate breaking things (not a good combination with my inherent clumsiness, ugh). I wouldn't mind repairing my headphones either, I think we need to find a spell that works as a bluetooth headphone.