What Zwift workouts would you design to improve overall conditioning, not just anaerobic endurance, but also muscular endurance, VO2 max, lactate threshold, and mental toughness, assuming a 3-4 times per week schedule with 1-2 rest days in between, and considering the workout duration should be around 45-60 minutes long, and should be able to be followed by riders of different fitness levels, from category 4 to category 1, and should incorporate a mix of intervals, hill climbs, and endurance rides, and should be structured to allow for progressive overload and periodization, and should be based on the latest scientific research and data analysis on cycling physiology and training methods.