Justin Rinaldi is a much better mid D coach than I am, but if I had to only use 3 workouts for the 800m and just easy runs/strides/weight room around it i’d do:
Workout 1: 4x50m flys, 4-5x150m w/ rolling start, full recovery
Workout 2: 5-6x300m @ goal 800m pace, just enough recovery to be able to hit pace but no more, this will advance from like 3:00-4:00 to 1:30-2:00 as you get fitter.
Workout 3: 4-5x3:00 @Vo2Max w/ 1:1 recovery
I mainly just disagree with the threshold work, lots of speed based 800m guys and even some evenly balanced 800m guys will be doing threshold work at 1:30-2:00 per mile slower than 800m race pace, and the running mechanics will be entirely different. Vo2max work strengthens your lactate threshold plenty, and will be more like 0:45-1:00 per mile slower than 800m pace which has you engaging the middle distance running mechanics and introducing race specific muscle fatigue a bit more. I hear of lots of 800m guys in that pro/elite caliber 1:42-1:48 range that never even touch threshold work and that leaves me to believe it’s not really necessary unless you also want to be running fast miles and 3ks. You’ll also really suffer a lot for the final rep or 2 on that vo2 workout I suggested, and I think there’s something important about being able to hurt for 3:00 when your race is going to land somewhere in that 1:40-2:10 range.