Season two was a huge improvement over season one. Season three has been a mixed bag thus far. The last episode was atrocious! Hope they get some new writers for season 4!
I thought it got a little better in season 2, but my spouse and I have not been impressed or particularly interested in S3 so far (we are two episodes behind, but apparently those have been even worse?). There was a time that I was too compulsive to stop watching something that got bad, but over the past few years I've been better and dropped some TV shows that I haven't been particularly into (Revolution and Once Upon a Time) - this one may be next.
It's a bit over-the-top in terms of patriotism and 'American pomposity', but it's very well made and some good action going on. As a lover of all things sci fi, I will continue to follow it. Good news about the renewal.