What is considered a good candidate for a crescent lift without implants?

Hello and thank you for your question.  The
best advice you can receive is from an in-person consultation.  Crescent excisions can accomplish minor changes in areola shape but do not provide much of a lift.   Make sure you specifically look
at before and after pictures of real patients who have had this surgery
performed by your surgeon and evaluate their results.   The most
important aspect is to find a surgeon you are comfortable with. I recommend
that you seek consultation with a qualified board-certified plastic surgeon who
can evaluate you in person.
Best wishes and good luck.
Richard G. Reish, M.D.
Harvard-trained plastic surgeon

A Crescent Turk breast lift can be performed to reposition the nipples slightly following removal of implants but in general I find that one should not for much more than a centimeter or so of lift. This does depend a bit on the diameter of the areola, a larger areola will allow for a larger list. It can be performed under local anesthesia and is a relatively simple procedure although discuss with your surgeon expected outcomes.

Crescent lifts can often be done under local anesthesia.  However, they are best for minor adjustments in nipple shape.  They are actually a pretty weak type of lift.  They tend to tighten one portion of the areola excessively if they are used to do anything more than a minor adjustment.
There are a whole array of available lifts, from around the areola to lollipop to full lifts.  It's important to perform the right lift on the right patient!