I would already start with ME. Try to find a good weekly volume which is not impacting your aerobic capacity volume and maintain this. You need to check if you can maintain ME during the ski trips since the ME effect from these are already pretty taxing.
Rationale: ME can accumulate over years. Anton Palzer for example is still struggling in cycling since he missed many years of accumulating cycling specific ME.
In 2024, you can then start to increase volume and intensity so you peak at your event. For the progression, I would rather concentrate on volume first and then weight since weight is limited somehow (joints, weight you can carry, lower back).
The backpack trip is too unspecific for me.
Not sure if I answered your questions.