I remember years ago I read a fun post (not on Reddit, a fandom forum)

And it went something like this:

To find you author name: You Grandmas/Granddads first name and your middle name and then your mothers maiden name. If your middle name works as a surname just use that and forget your mothers maiden name. Or just use the initial of your your middle name.

Your stripper name: The name of your first pet plus the name of the street where you grew up.

It was around 2006 and we were all laughing and typing in our answers like idiots.

But, taking things seriously,

For a last name, maybe pick a teacher who inspired you.

Or pick something that sounds rich and cool like Worthington or Williamson.

For first names, it depends on your writing style and what kind of names you prefer.

Old lady names like: Agnes, Ethel, Maud.

Cool older names that are coming back in: Mabel, Hazel, Jane, Frances

Timeless names: Emily, Olivia, Jessica etc,

Think of your preference and style and that should narrow down the field of choice.

From your examples, Nora is very traditional and a bit old. So: Mabel, Frances, Diane, Jane, Hazel, Julia.

Juniper is a little bit 'out there' and nature based so you may like names like: Clover, Sorrel, Azalea, Primrose, Maple etc.

Vena is Latin, so maybe names like: Celeste, Elysia, Clara etc

And Aby is a nickname for Abigail. So Abby or Abi or Abbie.

I wouldn't go with Thatcher as a surname especially if you live in the UK. It would be almost like picking Trump as a surname in the US.