I personally love disaster movies and Roland Emmerich, no matter how cheesy his movies can be (I even enjoyed his Godzilla, it's a nostalgic movie to remember my teenage years). I do feel some of the dialogues and acting were cringey (e.g. when Halle Berry talked about her love to her son, "Way more...way more..." (than the whole universe)), which is why I took one star, but I can't help but watching this movie again and again.
I love both leads, enjoyed the others too (the rebel son, his new stepdad, the babysitter, etc) but my favorite character is clearly John Bradley as KC, he's just truly adorably lovable (loved him since GoT). And I truly love the ending for him, too. I would like to have the same cool ending for myself (I won't spoil that here), being all alone in this world anyway, that ending is not bad at all.