No, you shouldn't. Voice acting is hard; a lot of games with professional voice actors do it badly too. A game with bad voice acting is a lot worse than a game with just text, and aside from which, I think the appeal of RM games is in that they are kind of retro, and even if you have good voice acting it will be incongruous with the fact that its 2D.
Anyway, you shouldn't be thinking about a sequel before finishing what you have now.