Working on my first novel today

Hey y'all

So its a hot Thursday night and I have had a long day at work, but you know what I want to keep writing! Naturally I am going to grab a large cup of tea and my laptop and continue work on my first fiction novel.

I've been thinking of changing my character's name.

So my two main characters are sisters: the eldest is Ivy who is beautiful, glamorous who is married to a rich Hollywood producer. She is an actress and model but because she has always depended on men all her life to provide for her, has never had to work hard. Nor is she a good actress.
The younger sister is Rosie, who is the complete opposite, a bookish corporate woman, working as a forensic accountant, who never wears makeup.

They were close as children but grew apart when Ivy went to college and got mixed up with the more high rolling crowd, eventually basing herself in America.

I am about 70% done but as always I am questioning bits and pieces along the way.

For example over the last week I have actually considered making the following changes:

-Changing where they were based: originally I made them based from San Diego, with the novel being set in Beverly Hills. I'm thinking of making the sisters originally from Sydney, Australia (where I'm from!) and making Rosie live there too. I originally had Rosie living in New York but I am thinking of seriously changing it all to Sydney Australia. I will still retain the novel being in Beverly Hills, as I have done a lot of research on the area (plus I want to go there!)

-Changing character name: I wanted to give both the sisters a plant/flower based name and I had intended to call the sisters Ivy and Zinnia. Overtime I didn't feel very connected to the name Zinnia and hence changed it Rosie.

What do you think, do you think these are good changes?

Should I revert back to my original ones?

I would love to hear your thoughts!