One of the steps backwards comparing to previous titles (X3) in my opinion was to leave shields generators out from ship chassis and totally rely on number of shield components that can be installed on the ship. Taking in to account that many ships have the same number of shield components they felt a bit samey in this regards. Some other aspects of shields also seemed like something that can be improved.
To fix this I implemented the following:
All ships now have internal shield generator that are mostly responsible for shield generational while providing some additional shield amount. They are mandatory and ships cannot be built/ordered without them.
External Shield components installed on ship provide mostly shield capacity and small amount of regeneration as a bonus.
All shields now always regenerate without delay
Fighting drones now have internal generator with small capacity.
Since 3.0 version of the mod all internal generators can be seen in shipyard/wharf UI and will be added as any other component to your encyclopedia when discovered.