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Like any complicated subject, it's really a lot simpler tham it seems to be.... once you strip off any fripparies and look at it from the right direction.
Top coupling, bottom coupling, magnetic coupling, inductive coupling, capacitive coupling, acoustic coupling by mechanical rods, acoustic in quartz, link windings, ports in waveguides... enough yet?
They are all just types of coupling. A way for adjacent resonators to share a little of each other's energy. Don't worry about the different types of coupling.
Set the Q of the end stages and then apply couplings from stage to stage to stage in a chain. Make the strengths of the couplings in a pattern (from tables in a book) and voila! your filter!
You can choose alternate ways of coupling to make life easy.
If you part-filled milk bottles with water as your resonators, and taped on lengths of garden hose as your couplers you could make a filter meeting a planned shape this way. Plastic rulers positioned along a school desk, coupled by rubber bands, anyone?
Spot the resonators, spot the couplers, consider the couplers. Look for the way of setting the Q of the end resonators. Look for the pattern in the strengths of the couplers. You can now read many important types of bandpass filters.
David