Most important thing for you to think about is why does this ranger follows party . And nat 20 on persuasion is not a reason . Write down for yourself clear goals that this character have and see which of those goals will he accomplish by going with the party . If there are no goals like that or when he will complete all of those he most likely will go on his own way . Maybe they will meet again after that and travel some more , but you always should keep in mind that they are together only for as long as it is interesting for everyone involved , not just the party . As far as mechanics go , I think you did everything right . You may even don ' t hold him back and go all out . I don ' t see why he can ' t use multiattack every turn if he can do it . If they are too low level themselves , just remove it altogether but dont just pull it out only when you need it that will feel like a cheap trick . Also note , that RAW he is now a member of the party and will get his share of exp , at least from battle encounters . So even if players don ' t pay him money , they are paying him experience .