Most advanced teachers want to say 'just go home and learn it', so then they can talk to you about the more advanced musical notions of the piece during lessons. This is the opposite of what I need - I'm not a good practicer, and I need advice for better practice discipline, techniques, and finishing a piece in a polished manner
It sounds like you are looking for a "technician." Someone that will give you the tool set of technique in order that you realize your own vision of the music. You don't want to copy a teachers interpretation, but rather acquire the skills that allow you to make your own discoveries in the music, pose your own questions, make your own claims. It would be helpful to spell all this out clearly when you interview a teacher. Let them know exactly what your goals are up front. Placing this all on the table from the first meeting will make for a more informed decision to whether or not a teacher and yourself are a good fit. I would also advise you to be open to listening to opinions and interpretations of your teachers, especially those that differ or which you may disagree with. You are under no obligation to agree with everything your teacher says, but it would be unwise to close your mind when an idea clashes with one of your own. It is great that you have recognized your vision for the music, but this is no excuse to dismiss an opposing interpretation. Being knowledgeable in the possibilities of music will only lead you to becoming a better musician. By its very nature music is not a fixed state: it can change, and it is a very beautiful thing when it does! Celebrate the possibility of having a multiplicity of perspectives on a given piece, and the possibility of changing them at any given time.