There are other shows on television that do the same thing. The Walking Dead is a great show where there are plenty of questions and only just a few answers even through the fifth season. It would appear that producers and directors have figured out that a certain group of loyal fans are happy with a little mystery and do not want everything spelled out for them.
The good television shows will take that mystery and spread it out for a couple of seasons, but at some point, it will be answered. The fans are going to start to disappear if you leave the questions out there unanswered. The ones that were able to get out of the dome last season and those that are still stuck inside will be featured in this season.
It will come down to who is going to work together with others and come up with a way to destroy the dome in order to free themselves from it. It would appear that all of the residents have the same goal, it is just a matter of how they are going to get to it.