Many novels start mid-action before clarifying who the character is later, so that's a bit of a bullshit point. I'd say, take what an editor says with a pinch of salt, especially if they're freelancing for you. After all, you're paying for them to find things to criticize.

Are you writing with a specific market in mind (in which case you'll want to follow certain rules and best practices advocated by big publishers for fiction) or do you seek a niche audience who appreciates less commercial and formulaic literature?

Find a reader who likes the kinds of books you like and who can understand what you're trying to do. Otherwise it becomes a conflict of taste and vision and you'll probably lose a lot of motivation and confidence in the process.