NPCs are much more interesting if they are slightly mysterious. An innkeeper is just an innkeeper, and will more or less be ignored by any party of PCs. But an innkeeper who seems to know just a bit too much, or an innkeeper with an unrecognisable yet strangely familiar tattoo on his arm, or an innkeeper who has several mounted monster heads and a couple of large axes hanging on his inn's walls... now that's someone the PCs will spend time thinking about.

The doubly cool thing about this approach to NPCs is that you once you've established it, you can invert it. All of a sudden the NPC who doesn't have anything peculiar or interesting about them becomes even more interesting...

Transcript

Yoda: ooo-OOO-oooh! Who have we here? {lights torch}
[SFX]: < pating doip squee bapo-kapgi-ding >
Yoda: Wendy of Luna-ma!
[SFX]: < oowoo squee blip >
{R2 tries to grab torch back, Yoda hits him}
[SFX]: whak whak whak
Yoda: Don't hurt Wendy, Doop Bug! Baron Barky smites you, he does!
Luke: Look, this is probably a lost cause, but is there any civilisation around here? Any buildings? Anyone I can talk to?
Yoda: Oh yes, lots. This way, this way! Love to meet you, they will.
Luke: Umm... If it's okay with you, I don't think I'll go back to your hut made of human skin.
Yoda: Be silly, do not, young Luke.
Luke: Wait, wha...? I never told you—
Yoda: As impatient as when you were born, you are. Waaa waaa waaa!
Yoda: This way.
{beat}
Luke: R2, guard the ship.
[SFX]: < doosquee boop ziting-bop bing fi-bapo-kapgi-ding bablip >
Luke: If I'm not back in an hour, scuttle the ship, hide at the bottom of the swamp, and wait for further instructions.
Yoda: Wow. A few wampas loose, your top paddock has.