Talking about the new leveling journey for Pokémon Go and its new level tasks prompts me that a good discussion can be made on the latter. Specifically, the discussion concerns the qualities of being "essential" or not, and being "avoidable" or not. These qualities, independent of the progression a Trainer can make on them, can then determine how they can be used by Trainers to level up or even defer that progression, the latter especially given that they earn lots of items in the process. Both of these qualities are then useful to be discussed for their relevance to the level tasks.
In this regard, "essential" refers to how necessary a task is to be performed in regular play, with or without the task in question. The task of "walk 25 km in a week" (an old task) and "trade Pokémon caught 300 km apart" (both old and new) are not really essential to be performed in regular play, but they do help with some of the gameplay. On the other hand, making Nice or better throws and powering up Pokémon are routinely essential in order to attain certain successes in the game, especially ones related to battling. For the level tasks, the essence is certainly to advance leveling progress, but they also help to make the essence of the actions in regular play evident.
Meanwhile, "avoidable" in this case refers to the possibility of not having to do a task and to wait for other or better opportunities before doing them, such as a task that when completed will surely result in going up a level. Any task has the potential for this, but tasks like "win 3-star Raid with Pokémon of CP 1500 or less" (also an old task) and "power up Pokémon to maximum CP" (old and new task) do quite exhibit a potential for avoidance. Then there are the tasks of exploring - even for long distances - and earning Stardust that no matter how much or little one plays, they'll eventually complete themselves, making them truly "unavoidable". Neither is leveling up, really, but progress can be paused at least for a little bit of time with some of these tasks.
Where and what does this leave players or Trainers? The combination of these two qualities gives a way for Trainers to establish how they can or will proceed with their level-up efforts. A less essential and more avoidable task can be saved (intervened) for last or whenever they really need it, while a more essential and less avoidable task is more likely to be complete itself without intervention, though not necessarily first. For example, the "crazy" players will likely have their platinum medal tasks completed unavoidably despite not being (too) essential, and more normal ones can try to save some for level-up holdovers when they get to certain high levels with tasks for them.
"Avoidable" and "essential" might not be the first thing one thinks of when describing the level tasks for higher levels, yet it does make some sense since many of the tasks are long-form in nature and end up furnishing lots of rewards when they are completed and the level increases. The tasks can then be factored into however and whenever one regularly plays Pokémon Go and be worked on accordingly with consideration of the two qualities above, and the effort becomes a journey in itself, even before and now after the renewal and replacement of those level-up tasks.
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