Also, here's my ideal Humanoid Book, which would be separate from the rest of the monsters. (Separate in this case can mean "it's own chapter in the PHB or MM")
Step 1: Create a whole ton of NPC statblocks for every tier. Make them both as generic and as flavorful as possible. Yes, it's a weird combo.
Step 2: Write up the humanoids. For each one, do the physical description, a bit of lore, and three different example mini-cultures (no more than few sentences for each--these are examples designed to get the GMs and players to think). The cultures could be anything from "The Nation of Gnomingrad" to "the Brass Orc Mercenary Company." One culture should be evil, one neutral, and one good.
(See, my biggest problem with alignment is that no matter how much the game says "usually" or insists that any particular race doesn't have to be the listed alignment, they almost never actually take that into consideration in their actual books. This way, even if the description says "this species is mostly one alignment, there's an "official example" of a way to include variants.)
Step 3: For each of these humanoids, include both the PC stats and an NPC template. The NPC templates can include stat modifications, even though the PC stats wouldn't. This should hopefully satisfy both the people who think that one particularly strong PC halfling means that all halflings will also be strong (nope, their NPC template says they get a -4 to Strength; the PC halfling is just unique), and those people who need or want guidelines for where to assign their stats.
Each humanoid would take up a page, maybe two if there's a lot of art involved.
Then, to make an orc knight or elf raider or grung druid, you put the appropriate NPC template on the statblock.
Does it mean that you can play one right out of the book? No, there's math involved. However, so much of this is done online these days via DDB or a VTT that one of those will do the math for a large number of players, and hey, it's still easier and faster than what was involved in 3e.