You may be able to get away with:
You get an inherited SMC, but also a full graph, variables, sockets, functions and so on. And all that without the overhead of a full-blown actor; and, most importantly, you can avoid pigeonholing yourself into relying on Child Actors.
Probably irrelevant if you have 10-20 pieces. May become relevant if you need 200 pieces in 20 ships. Look into inheritance if you’re not familiar with the concept, components support it; and exposing variables, too, thanks to this pretty node (Add Component by Class added in 4.26 or 4.27):
I’ve build modular mechanical entities with this. It also works with skeletal mesh components. The only (can be major) drawback is that components cannot own other components - but that’s what socket attachment is for. Whether it is a drawback depends on how you organise and build stuff.