When analysing any sport, identifying the plane/s of motion that movement occurs in is very important. The majority of movement and force production in skiing occurs in the frontal plane or side to side. Training for the sport should reflect this.
It can be difficult to create that lateral force production in the gym but to maximise frontal plane activity, unilateral lifts and loads really come to the fore. Which is also really handy given the rarity in skiing that force is the same through both legs. Multi directional hops, jumps and drop landings all with clean takeoff and landing mechanics should also form a part of any ski training. These also include a big eccentric component that we already know to be important.
As for the conditioning side, long duration steady state exercise seems to be a popular method of preparation. Circuits and shuttles, however, with changes of direction provide a massive amount of versatility allowing a lot of frontal plane movement to be used and allowing the possibility of training other balance and reactive skills under fatigue. They also have much more crossover biomechanically than a straight line activity like running and cycling.