Reaper has become the “new” norm. This was predicted by players when it was first announced. Being that this is the case I would like to make some suggestions.
We play a game called “Dungeons and Dragons” and that a significant aspect of the franchise is to play in dungeons and fight dragons, among a wide variety of other enemies. For me, reapers in dungeons appear to be a very crude “mechanic” used to increase the difficulty rating and their inclusion stands out as something very unlike what one would expect to see in the franchise.
Perhaps, at this stage in game development reapers could be integrated into the local dungeon eco-system better. For example, in a dungeon full of kobolds, a Fear Reaper could be represented as a Fear Reaper Kobold etc. I acknowledge this may be only a cosmetic change, however from an integration perspective, I think that this small change may re-align the crude introduction of the reaper system and make it appear more natural.
Further, there may be some merit in expanding on the abilities of reapers if they are integrated into the eco-system where reapers also share the unique characteristics of a particular monster. For example, we might get a Doom Dragon Reaper which not only includes all the characteristics of a Doom Reaper but also of a Dragon.
Finally, on killing these kinds of high end reapers, there could be the chance that a chest may drop that could contain threads of fate or reaper fragments.