Personally, I'd rather see a setting where all intelligent nonhumans are either descended or transformed from humans.
Rather than having things like liches, depending on their emotional leanings, powerful mages who have learned the secret of immortality might slowly transform themselves into things like dragons (pride), beholders (paranoia), illithids (hunger for knowledge), or elves (vanity).
Things like orcs, goblins, dwarves, and halflings are just races of humans.
Orcs evolved from tribes of rapists, so lost their beauty and charm in favor of brute strength. Goblins evolved from tribes that followed a Marxist-like credo of "from each according to their ability, to each according to their needs" so obvious strengths became burdens and were selected out. Dwarves adapted to mining. Halflings lived in peaceful isolation, so they lost their size and strength, but remain decent and affable.
That sort of thing.