First of all, this show is a comedy. Some reviewers don't seem to realize that.
Those who criticized the performance of the kids in the pilot have a point. They were over the top. But that is a very small part of the show; in the second episode, the kids barely show up.
But Debra Messing is very enjoyable in this show. Imagine Kate Beckett without Castle. It's the same type of light comedy mixed with real crime mysteries. Even when Laura is mixing it up with suspects, she is adorkable and fun to watch.
She wants to get her soon-to-be ex out of her life, but they work together, so she must endure his personality on a daily basis. This seems somewhat trite, but they pull it off. Her other coworkers are quirky, so the tone remains light. I enjoy it.
Update 10/31/14: Now that we have seen a few episodes of this new show, it is consistent in its humor, while presenting actual crime solutions. But this is not "Elementary", so don't expect much more than light fare. Robert Klein just appeared as Laura's father--a great casting coup!