Athletic Cyberleg design (need both):
Would be based around this design (http://fichtenfoo.net/blog/completed-the-hare/) and those of disabled track stars of the modern era. They would replace the lower legs of the person installed with them, and would provide a slight boost to how fast a person walked room to room (which is based on stats, but I think would be easier to differentiate without having to overhaul the system). The speed at which they boosted you would be based on quality or the model if those were available, and would be pretty basic.
Heavy/Old Cyberlegs/Arms design:
These would be either very old clunky models, or specifically for corpsec who need the extra staying power. These would cause you to sink faster in water, not be able to dodge as fast, and would not look like a human leg (very obvious: charisma debuff?), but would cause the person to weigh more and maybe would help resist being dragged away by someone grappling.
Flashy Cyberleg/arms Design:
These would be close looking to real arms, and either chrome or flesh toned. Possibly they would have an implanted watch in the arms, something else in the leg. They would be both to replace limbs and to make life easier on the person. These would be expensive.
Would act similar to a glovebox or locker, but could only hold certain sized items (pistol, quick term, or e-note size or so, nothing big) and would shroud it from some sensors. These would be highly illegal and expensive, have no other benefits besides being able to smuggle an object into a place it was needed. Would be awesome for assassin/terrorist RP, along with undercover corpsec operatives and smugglers.
These would be similar to the Nailz and SynthKnux that already exist, but maybe have an extra damage boost to the combat they do, given the obviousness and expense. The Nailz would be more like Wolvers from CP2020 and practically the size of knife blades, and the synthknux could be like Spurs from Shadowrun, with spikes in the knuckles causing piercing damage or similar. These maybe would only be available through corporations or various underground factions, and would be a higher level version of Nailz and SynthKnux.
Let me know what you guys and gals think. They are just some of my favorite cyberware things from various cyberpunk games I've played, morphed to fit Sindome without being overly overpowered and ridiculous.