The Factory
This is where Neziki lives, so I thought I might as well describe what I think the place is like.
So yeah, metallic, sci-fi futuristic sort of aesthetic. I don't even know if he's got any carpet in the place; it's all cold and generally not very welcoming. I imagine that before he became Factory Head, the building used to be pretty bland and regular, but he spends some of his free-time every now and then modifying it and adding cool things. This inculdes: conveyor belts, secret underground entryways for him to appear from, cameras, cool glowing things that are totally practical somehow, and a really impressive shelving system with automated claw hand things and conveyor belts to move Pokemon efficiently around the place.
The building may or may not secretly be a giant transformer robot (I mean come on, why else would it need such gigantic fans on the side?), and I imagine it has this really complicated maze-like series of underground levels that only Neziki knows how to navigate completely. The lower you go, the colder it gets.
In the game you see scientists helping challengers through the factory, but I like the completely autonomous Pokespe interpretation better; challengers are toted around on conveyor belts and debriefed on procedures and swapping by automated LCD screens rather than actual people. I take it there may be factory workers during certain times of day, but as an effort to keep the place running as close to 24/7 as possible, I'm sure Neziki keeps the factory in autonomous mode for the majority of the day. He prefers it like that anyways.
As a side note, I kind of just automatically assume that the place has got a bedroom and kitchen somewhere in the lower floors. It's just as metallic in there as it is in the rest of the factory, though. I bet Neziki's room is crisp and clean with a bunch of gadgets organized on shelves or laid strategically on certain spots of the floor.
Fig. 1 _CONVEYORS
Fig. 2_MOTION SENSING LIGHT-UP FIELD (and who knows what else Neziki has installed in here)
Fig. 3_AN EXPLOSIVE ENTRANCE
Either he can teleport or there's some hidden panel under the ground there.