Adding more tension to "gyms"

[milkyroute]

The idea is to remove Gyms, and instead make the equivalent of the "gym leader" fight the player at the end of a difficult route filled with wild OpMons, puzzles and trainers (usually in the big wild areas so it's coupled with exploration) so it builds tension because if you want to heal you have to return to the city and the boss at the end creates a tension spike, so the player is really involved in the game.

Arguments evoked on the Discord server:
Why not just have the difficult route/challenge you proposed but inside the gym?
Two reasons:

1. It prevents the player from just leaving the gym and having to walk 5 meters before healing. Here, if the players wants to retreat, there's a long way back, so more tension.
2. It highlights the landscapes of the region and the exploration feeling. Plus it gives a use to the big wild areas other than being a secondary quest (even if some will be used by the team)