Usually I prefer to avoid inflicting my dire drawing skills upon y’all, but what the hell, I’ll make an exception this once.
The diagram to the right is my quick size sketch of the aforementioned Nelyn-class modular cutter (in blue) and the Élyn-class modular microcutter (in green).
As you can see, the Nelyn is the big one, inspired by/a harder version of the Traveller RPG’s modular cutter; an interplanetary craft that’s the workhorse of the Empire; 8 m in diameter, and 48 m long in total; an 8 m main hull at for’ard for the flight crew, the 16 m module space; a 4 m engineering hull for sensitive machinery; and the 16 m propulsion bus at the back. The module space is bridged by three trusses 120 degrees apart, the dorsal one of which is split in the middle and folds back to allow module swapout. And there are lots of different modules for pretty much any purpose you can think of.
The Élyn is the smaller one, only 4 m in diameter and with a 6 m hull (including engines), optionally taking a 6 m cylindrical module in a rear-mount. It’s strictly a local-orbit craft without interplanetary capability (although it is capable of take-off and landing on many planets) – but the reason it’s drawn where it is is that there is a Nelyn module specifically designed as a cradle for the Élyn, letting an entrepreneur with the former make pretty decent money providing a taxi service for the latter on long trips…
Because despite this and this, there are always a few modifications once you actually start beating brass and doing detail work:
The 4 x “Slammer III” dual turreted mass drivers have become 2 x “Slammer III” duals and 8 x “Slammer III” singles, four up front, two in radiator-tip (wingtip) leading-edge mounts, and two rearward-mounted to protect the ship’s kilt;
The aft landing bay door is now dropped and replaced with two side-opening landing bay doors for’ard of the radiators, since the former would have required flying directly through the high-radiation zone of the torch drive and said thermal radiators to use; much easier to fly parallel and dock sideways. This, in turn, has enabled the transformation of the back of the landing bay into dedicated cargo/storage space, with said side doors being in an excellent place for loading when the ship is landed or docked.
And after consideration of the practical height of the landing bay vis-a-vis the size of the Nelyn-class modular cutter, I’m swapping it out for a pair of Élyn-class modular microcutters (a gig-sized craft); if you want a really pretty good visual reference for that, think of it as looking like a rebranded SpaceX Dragon V2, with the cylindrical module in place of the trunk.