Frankly if you are looking for a local guide I met Bounthieng by chance who has a motor boat on the Mekong. He works for the agencies but you can contact him from Christiane he will make you a private visit where you want and will explain many things to you. I spent a morning with him he is adorable! He seeks to improve his English and loves to chat with tourists and share his experience.
Do not go to Luang Prabang without seeing it !!! You can contact him on whatsapp I don’t remember his email. His name is Bounthieng tel. 02098274140
He is a very good man.