Well not much creativity here I see, but I have had an idea in mind for some time and I think you'd be interested.
The protagonist of the game would be an elf with a party made of humans and other races some with a lifespan around humans, less or even a few centuries, the elf would be immortal. Your goal would be to save the world, stop apocaliptic events and things like that but only big missions involving events that happen once every few decades or every century.
But after the battle is won all party members would return to their normal lives and time would fly by. For the next event that needs to be stop or the next time the world needs to be saved there would be a member of the party who died from old age and everyone would grieve him, the elf not more than the others particularly. However as times and adventures go by the rest of the party would start to die from old age too leaving the elf protagonist alone.
Despite winning all of his battles he would end up losing all of his friends (that he could also see as a family) because they would die of old age. And depending on the choices you made he could either learn to move on and keep enjoying life and cherish the time he has with his new loved ones or be consumed by grief and isolate himself forever.
I feel this would work so well with elves as in my opinion they are the best race to tackle themes about loss and the passing of time.