Nancy Nigrosh, Instructor at UCLA Extension Writers' Program (2013-present)
Natalie, you can answer this question far better than I could because the answer is unique to each person who asks it, based on what you might consider “best” for your particular needs as a writer.
Agents aren’t one size fits all. Pretty much every agent specializes in representation of authors in a particular writing category or genre. Agents also have individualized needs in terms of potential clients – given time and resources already committed to current clients.
You can create a list of authors you admire - whose chosen writing type is similar to yours in some obvious way, find out who represents those authors, and you’d have the kind of list I think you might be looking for, and you may discover that a number of those writers are represented by agents in lots of locations other than Manhattan.