Doing impressions of famous people is a good way to come up with different voices for speaking in character as various NPCs. You can imagine in your head that the blacksmith is Sean Connery, the priestess is Cate Blanchett, the tavern keeper is Christopher Lee, the sassy barmaid is Whoopi Goldberg, and the bombastic mayor of the town is William Shatner. This gives you a hook to getting the voices consistent each time you need to play one of these personas.

And it doesn't matter if you suck at impressions - in fact all the better, because then your players won't have any idea where these ridiculous voices are coming from.

Transcript

Han: Hi, Annie'll be here in a second.
GM: Okay, we're all here on this end.
Leia: Sorry, just finishing up my latest video.
C-3PO: I've been showing all my friends in engineering. Everyone loves the singing impressions. Especially Christopher Walken.
Han: Christopher Walken is doing engineering?
{beat}
Leia: I've almost got enough followers to start making some of Jim's money back.
Han: I'm an investor!
Leia: Almost a successful one, even.
Han: We've been successfully invested in each other for years, sweetie.
Luke: Oh my god, get a room.
Han: Like this one?