Geas
Meat Thing
... A thought. Taking into consideration the particulars of Bentusi radial hull design, I figure that there are two possible options for shoring up weak spots: either doubling down on specialized drone ships or disposable/detachable modular pods. We already know the downsides of the former. The latter though... unfortunately I can already think of at least one major downside: efficiency/effectiveness. a self-contained module probably wouldn't be able to draw power from whatever ship it's bolted onto, not without compromising hull integrity. As such, it'd likely be a good deal more expensive than something physically integrated into a ship-body and in many situations, not nearly as effective and might actually be a hindrance for normal operations. But in an emergency, such a thing might be useful in a pinch. Ugh, it's a terrible idea, but it might be less terrible or even possibly useful if the strap-on pod contains the right equipment/system, like an emergency shield projector perhaps? a modified drone might work better in that regard - in a pinch it could fly over to such-and-such Bentusi craft, latch onto the hull like a robot barnacle, then activate whatever system it's carrying.