Balance is not a factor you need to consider here - free archetype makes PCs slightly more powerful, but doesn't really change the math or action economy of the game enough for encounter building to be affected.

Like others have said complexity may be an issue, but to my eyes the only risk is that new players either get overloaded with options - which you could help them with - or forget to use their new abilities. Forgetting things could make them feel bad or overwhelmed, but they probably won't even notice and it most likely won't affect their enjoyment of the game one way or the other.

You know the new players better than we do and therefore have a better idea of how much complexity they can handle. But I think concerns about complexity are a little overblown. Not negligible, just overblown. You could always test it on one group and not the other, lol.