If ABC is a necessary technical feature, it can only be put in the exclusive right at the same time, otherwise the technical scheme will be incomplete, and it will become an invalid reason and will not play a protective role in the future.
If you want to protect the product in an all-round way, you should consider some variants of the product, such as the ABC features you mentioned. Will similar features also realize this invention? Write out all the easy-to-think alternative technical features, rather than breaking them into small parts, which is the real comprehensive protection.
In addition, if we have to split ABC's features into three patents, we suggest writing them into three different products. Background technology, instructions and other aspects can be irrelevant, but how to write as a single product.