How specific does my research interest need to be?
Concrete enough that someone in the field recognizes it as a question rather than a topic. Not a thesis proposal, and not just an area name. That distinction is usually the biggest single improvement available in a draft.
This comes up on Statement of Purpose Editing, where it is answered in the context of the work itself.
Not what you asked?
Ask us the actual question
Send the draft, the rubric or the score report with it. You get a real answer and a price before you commit to anything.