Somewhere someone mentioned the issue of Tracking as a feat--I'm wondering why it shouldn't just be a skill, like Survival.
One thing I wanted to emphasize here is I don't see Gnomes as particularly Charismatic. No race gets Charisma addedd AFAIK, which suggests no race should get Bard or Sorceror as a favored class.
I come to this as being a big fan of Gnomes, particularly the 1st edition flavor, and use Bards extensively as NPCs IMC.
Bards are quite prevalent in all the human cultures there. Everywhere you go someone is strumming a harp, singing a lay a capella, telling a story, or reciting poetry. It is rare that a tavern is bereft of these. One group of newbies to my campaign walked around the town from the hinterlands where they grew up and kept trying to ignore all the bards (LOL!!!) everywhere because they were afraid they were trying to cast Charm Person on them or something.
Anyhow, the point is, I come from this from a pro-Bard, pro-Gnome perspective and I don't see how Gnomes would favor this class. There are Gnome Bards, but most of the Gnome NPCs are Jewelers, Botanists, Fine Furniture makers, Gem Assayers and the like. The adventuring types are split evenly between fighters (using hammers and picks), rogues and illusionists. There are some clerics and druids, and some gnome rangers in their homelands.
But back to the topic. Of all the non-human races, I think Half-Elves would be the most acceptable, or perhaps Haflings. Charisma wise. Halfings however I think 80% of folks would say naturally make great Rogues. Half-Elves don't really have a particular niche, being like humans generalists. Though I am very Tolkien-centric, and always tend to think of Rangers as Half-Elves as natural.
Course the other major Half-Elf (correct me if I'm wrong) in those stories was Elrond, who was a kind of Aristocrat, with some levels of Fighter and Wizard, but seemed to know a lot of Lore--perhaps some Bard levels too? And then there's the fact that Aragorn knew some poetry too. And the Haflings too. And the Dwarves at the beginning of The Hobbit. The fact that the Trolls knew some British working class limericks suggest possibilities for monsters having some levels of Bard, if low, too.