@Verdinut
Indeed... everything you said is spot on, and as I understand it, everytime you add an XO point in a passive design, you get many more challenges in making the different bands work smoothly together. I do not know how a hybrid Active/Passive interact.
Either way, cabinet complexity is also boosted significantly.
The Alden book is one of my favorites, a very worthy read. For those that need an easier introduction, the Weems and Murphy books are great getting a more basic understanding.