It's not the "dead" elves I feel sorry for. They get happily reborn and healed up. It's the ones who linger, mourning, and guilty. They've got it tough.
Although, with Feanor and his sons-- and Miriel-- refused permission to be reborn by Mandos, they have it tough too.
But not the average reborn, reincarnated elf. What's to pity?