i can find no help in the rule book. so if i give him the devoted servant and he take a card during the day does he retain the actor powers? it could be over powered but there aren't many good cards for the actor to take. i think i am going to make it so that if he use the servant's power he would lose the rest of his cards.
It is my experience that the rule books provided with the games are more like guidelines. You can adapt the game anyway you want. If the rules don't provide you with an adequate answer: make one up.
For example I've played the 'multiple villages'- variation and had to sit down with a couple of moderators to come up with solutions for some problems that could occur and which the rule books said nothing about. Your question about the actor falls in the same category as the problems I faced preparing for multiple-villages.
You already gave an excellent solution to your problem!