The current game flow, where players switch drone upgrades to optimize a specific activity diminishes the 'pack opening' experience in the Overworld and leads to frustration when players forget to adjust their drone upgrades before traveling to a region. But most importantly, it oversimplifies the OW gameplay, as players mindlessly collect everything that aligns with their drone's upgrades. Players should have the freedom to collect whatever interests them, rather than feeling obligated to target specific activities based on their drone upgrades each run.
The current drone upgrades system lacks depth and re-craftability. This could be enhanced by introducing additional random mods to the upgrades. Adding +1 random mod per stage would be a good starting point. Furthermore, increasing the number of slots to accommodate more drone upgrades would provide players with greater flexibility and customization options.
4000 energy per travel doesn't feel that bad but there's always some parts of the heatmap left to explore even with reduced activity costs. Increasing the number of drone slots could help mitigate this but we could also introduce a new upgrade that increases the energy per travel.
I think an extra 500 energy would be welcomed through a drone upgrade. This paired with the Ergon Rifts would basically make a total available energy of 5000 per travel.
Drone Energy Upgrade Stages:
Stage 1: + 100 Energy
Stage 2: + 250 Energy
Stage 3: + 500 Energy