First of all, you need to ask yourself- “How much flexible and open to changes I am in my manuscript?” If not much, it does not matter even if you take the most premium editing service, and are assigned to work with an editor holding expertise in your genre, you won’t be satisfied. The thing is, the editor is going to be your best critic. And if critics and suggestions make you uncomfortable, go with copyediting.
Go with line editing if you are 100% satisfied with your plot and only want editing to contribute to make it the best version of itself.
But if you are highly open and flexible to changes, and could do some hard-work with your editor to shatter all boundaries and barriers to think out of the box to give your ideas some wings, go with developmental editing.
And even then if you are confused to decide the type of book editing, you need not worry. Send us first few pages of your manuscript, along with the sample edit, you will be provided with a package designed specifically for you direct from the editor’s desk.