Suggestions may need to be done for different types of equipment and software, as well as some various prices, like the best mikes under $x, ect, and software to alter voices may be needed since I would assume most here have adult sounding voices and the main focus, if done like in the movies & tv episodes, will be kids, with the adults not having lots of appearances in some scenes.
Also, depending on the number of voice actors and who plays what some roles may need to be removed or altered a bit since are likely going to be far less females to play female roles, especially the adult females Tria, Grandma Longneck, Ducky & Petrie's mother. Though in Ducky's case her father could be used maybe, since he's not mentioned as being dead, or someone who has practice could do multiple roles and alter their voice themselves or use software of some sort.