First of all, I would like to thank you so much for taking the time to write such a detailed review and feedback! Comments like yours are invaluable to allow us to make better games so I will say it again: thank you! <3
Now some pieces of information from the inside. We definitely know the controls are far from perfect, we noticed it when playtesting and it's one thing that reviewers told us a lot too. We've been brainstorming of sorts since then to try to rethink the controls but we haven't found a perfect solution just yet, something to keep an eye out.
As mentionned on the game page, playing on Firefox in fullscreen leads to weird hitboxes offset for some unknown reason, maybe you being more comfortable in "windowed" maybe comes from that? But the global detection of the pointer and objects hitboxes is also frequently brought up by testers (and we totally agree!).
Finally, when a ghost's energy is fully depleted, he is kicked out of the object it is currently possessing. maybe the lightning icon was a bad choice because it's hard to see when very low on energy because of the narrow shape of the icon. There is alternatively the gauge in the bottom left corner. But now that I'm thinking about it, maybe the ghost should be kicked out as soon as it drops below the energy cost, something to keep in mind and heavily test.
Anyway, enough rambling, thank you again for your very nice comment and feedback, rest assured that it is very appreciated and really appreciated! :)