@SilentKitty @kochamkluski
I like the idea @dannydanbo mentioned where the ectoplasm is more like the vampire energy bar - it gets drained and then slowly replenishes. Nor sure what the best way to do that is, but I do like the idea of ghosts becoming more sluggish and finally disappear when their energy has drained. So ghosts won't die or anything, just become really sluggish and invisible and powerless. Maybe there could be a poetic thing going on where ghosts 'step into the twilight' to recharge - they're not sleeping, just slightly not being there, or being 'in between' light and dark. Yeah, I like that! Almost like they're resting in a soulful kind of way in the dust in light beams. :) Then they could replenish the activity bar by interacting with the living world again until they need to 'step into the twilight' again.
But it would be cool if ghosts could 'find' ectoplasm around the world, and it would be only visible to them, but they could find it all around, but there would be an extra amount in the graveyards - on the ground, on tombstones, on urns, on trees... etc. That way they could prolong the time until they have to 'step into the twilight' - much like Sims drink coffee, but instead ghosts 'absorb' ectoplasm they find around the world. :p