I'm Mah-Gus all the way. Everyone I know in person (who knows what CT is) says it the same. I could care less if people say it differently. Same with Ayla, Marle
What bugs the hell out of me is the K sound that gets shoved into Schala's name. Ugh. And anything where Lucca is not "Luke, uh".
I pronounce Serge Surge. I don't have a problem with other pronunciations but I don't understand why people call him Sergio. That's not his name. IRL I have a friend named Jim. Not James. Jim. Says it on his birth certificate, license, etc. But people think they're clever and try to come up with nicknames and "James" inevitably gets thrown in there. He's never been James. Just like Serge has never been Sergio.
The name I go by is Addie in real life. It's an odd name for a male, and people mispronounce it ALL THE TIME. My upstairs neighbor has been calling me "Odd E" for about a year and I can't just correct him now. My license plate has a phonetically spelled version of my first name, which I blame for my neighbor's confusion. He's not reading it right. I've been called all kinds of names though. Abbie, Eddie, Andy, Allie, Daddie(that was a weird one), Paddy, Adding. My go-to explanation is "it's like Eddie but with an A".