The problem I face is committing to the title, along with the cost of the ISBNs. I don't want to make a mistake that affects the series as a whole or the new subseries / series. It's a nonfiction series, which I guess may or may not matter.
Should I jeopardize my series title and following by including in it a subseries? Or should I simply make it a separate series (even though it is really a part of the established one)?
Is there another way to go about this? Where a series of books is part of a whole series yet forms a series of its own so that I can title the books in the subseries from Book 1, Book 2...?
I have a series of nonfiction books that share the last two words in all the titles. This two word phrase sums up the main direction and focus of the books. So far there are four books in the series. Each book in the series has a different title with the two word phrase added at the end. What I want to do is add another five to ten shorter books that also use the last two word phrase in the three word titles. The titles will all be the same, but I add Book 1, Book 2, Book 3, etc at the end. Actually, the 'Book...' bit is under the three word title like it was a subtitle (but not a subtitle).
The main problem with this setup that I can see is these five to ten new books will dominate the four books. People may not even see them in the back catalogue on my author page. I'm not sure if this is the right way to go about doing this, hence the idea of setting it up as a subseries. So that Amazon sees it as a subsection(?) within the main series but still gives it it's own series page.
Here's an unimaginative example, but it will do. You have a series titled Burger Recipes with titles like On the Run Burger Recipes (Burger Recipes Book 1) and Fantasy Island Burger Recipes (Burger Recipes, Book 2). You want to write a book about meatless burger recipes and you have enough enough ideas to make a five book series with titles like Delicious Egg and Bean without Meat Burger Recipes, American Style Without Meat Burger Recipes. This another series with the last phrase in each title being Without Meat Burger Recipes
Would I do best to treat these as a subseries? With titles like these: Delicious Egg and Bean Without Meat Burger Recipes(Burger Recipes, Book 3), American Style Without Meat Burger Recipes (Burger Recipes, Book 4).
OR create a new series? Titling this way instead: Delicious Egg and Bean Without Meat Burger Recipes(Burger Recipes, Book 1), American Style Without Meat Burger Recipes (Burger Recipes, Book 2).
Thanks in advance for your suggestions.