The interior of the ssupd Xhuttle has the motherboard at a 90-degree rotation at the top. The reason for the bulk are those previously mentioned routing channels for the cable as all wiring that is usually external is routed internally to the back and then outside the confines of the enclosure. The Xhuttle has all the cutouts for a BTF board as well, with no components like storage or the PSU blocking these.
Unfortunately the use of unnecessary plastic continues on the interior with a horizontal cable cover below the motherboard. ssupd hides the PSU and some storage behind that solid section, but has left the top of it completely open as a means to allow for the routing of all the wires. It would have been nicer if there were deliberate openings instead, which would then eliminate any necessity for that cable cover. You will also find a metal GPU support bracket which won't be of much use in the "D" stance. While it won't be in the right spot for the "U" setup, ssupd has thought of that, with a screw mounting hole in a different part of the case to properly benefit from this component.
On the floor of the case, you will find three 120 mm fans with ARGB elements in their hubs which hold reverse fan blades to pull in air from the underside of the chassis. They use a proprietary 6-pin wiring and are daisy-chained cleanly out-of-the-box. Fortunately, the interface at the other end of the cables is PWM and ARGB, so you should have no issues with integrating them into your setup. These units are mounted on a removable frame identical to the one also present in the rear of the Xhuttle. This means you could install 360 mm radiators on both of these at the same time. Looking at the ceiling, there are the seven expansion slots, with removable covers which are held in place by classic screws. Instead of holes to mount a fan, ssupd has included ones to allow for pumps or reservoirs to be attached instead.
In terms of storage, the ssupd Xhuttle is potentially capable of up to four drives. The larger plate behind the CPU socket has space for two 2.5 or 3.5" drives. Alternatively, you can mount a 120 mm fan here instead. Then there is another tray in the bottom right corner of this chamber that can hold two 2.5" units or one 3.5" drive. Besides that, you will find a simple but functional PSU bay, with plenty of room for longer variants.
ssupd has also peppered the entire interior with Velcro strips of different kinds, which should translate into some excellent cable management results during assembly. The only oddity is that it feels like there was one missing at the very back position, above the two biggest variants.
All the cables inside the ssupd Xhuttle are sleeved black and the USB 3.0 Type-A connector employs a flat-band wire, but the USB Type-C does not, unfortunately. The audio cable has some black tape around the end of the sleeving to hide the colorful cables. While this is well intended, it doesn't look particularly good either. On the upside, there is a unified front panel plug, making this step of wiring up the chassis a breeze. Lastly, there are a few wires in form of a SATA power connector for the ARGB strip in the front and the embedded controller. An ARGB connector allows for motherboard control and then there is the PWM plug for the three fans, which is spliced off that proprietary 6-pin flat-band cable the fans come with.