If you look at 3PP games like
Nyambe, Northern Crown, and
Swashbuckling Adventures, and even WotC's own
Forgotten Realms to a certain extent, they break down humans into countries or regions, each of which have their own unique stat adjustments and even Feat abilities.
It works quite well for humans, but there is no reason you can't have similar variations for other races, which will give both you AND your players a wide selection without "Baskin Robbins-ing" the races. You could thus have, say...6 races, but as many variants within them as you have countries.
Dwarves, for instance, who live largely enslaved in the mines or cities in one region might have different stat adjustments and even racial familiarity (more Picks, Mauls and Hammers than Axes and Urgoshes) with weapons than those who grew up in a still independent mountain keep 600 miles away.
IOW, many of your "sub-races" would be reskinned as "ethnicities," "tribes," or some other kind of regional variant. Those 2 kinds of elf would really be one, only with cultural differences distinguishing them.
Only when you have something truly different- like Elves (or Gnomes or whatever) fully adapted for living underground, underwater, or even another plane would you truly have "sub-races."
Some might see this as a difference without distinction, and to an extent, they're right.
However, going with "culture" rather than "sub-race," you gain the advantage of being able to introduce new kinds of Elves or what have you without having to ret-con your campaign to explain why these guys just showed up. The fact that your party has wandered far and wide would be explanation enough- Gnomes from 2000 miles North or East or West or South of the campaign starting point may well have truly alien cultural values and skillsets as compared to those the PCs would be more familiar with.
gnomes are little people who polish stones and lend money but mischievous fey the live in camouflaged towns.
One idea I've been toying with but haven't implemented is developing a "Fey" template of some kind, to simulate those who have a true connection to that otherworldly realm. Its not for every type of campaign, but still...
For races like Gnomes and Elves, "Fey-template" individuals would be greatly respected as representatives of what they used to be.
For Humans, though, the "Fey-template" might simulate the Changelings, or even those with faerie blessings.
As for the template's exact nature, I haven't worked it all out, but I currently envision it as granting additional proficiency with arcane magic- the PC picks a school to get a DC bonus or some such- while also adding Geomancer-style Drift to the PC.
In addition, though, they gain a vulnerability to Cold Iron, and (probably) have a 1-step smaller HD/level in their classes (d4 becomes d4-1)