Hey @anastasios! So if you don’t like how the default fonts look, you can add custom fonts that work more with Greek. This can be done via the custom CSS section of your blog. Here’s a forum post on how to use custom fonts:
For a start, it looks like Google Fonts has a good selection of Greek fonts to choose from. I am sure there are other resources you can use (and if anyone knows please share).
Hope that helps!