I'm not sure what all of those are. There are probably exceptions, but given the definition of a species they're very, very rare.
I've always considered dwarves and orcs or elves and humands to be separate races, not species. more like the difference between a terrier and a rottweiler than the difference between a lion and a tiger.
I'd prefer it if half of the raws of each parent were randomly chosen for each child than a new one is created for each half race. it would take a lot more work to figure out but it would be a lot more flexible. not everything should randomly chosen, it should be based on logic, and there should be some raws controlling what could mate with what and how often it happens. maybe each tag could have a separate percentage on how often its chosen. so immortality would be rare but pointed ears would be common if you're dealing with half elves. maybe be considered similar to dominant and reccessive genes. though a bit simplified.
to have this work effectively you'd probably need a lot more tags for each race to up the diversity. but most could just be cosmetic.
So, yes, after a while the world would be made up entirely of hybrids, but whats the difference between a human and a human who likes fighting. the fighting tag/gene could come from an orc or whatever, but after ten generations they'd look like humans and have the stats of humans, it'd just be a random genetic trait.
of course you'd still need to make relationships between different races very rare to stop it from becoming a complete muddle. but that seems simple. a full blooded creature would only have a 1% chance of mating with enough race. a half blood would have a fifty % chance with its two parent races, a 0.5% chance with another race. maybe a five % chance with another halfblood to make it interesting. a three quarters would have a bigger chance of mating with what gave it the three quarters. if its less than half for everything than it'd have a bigger chance of mating with another mongrel.