okay, kill me, but I actually liked HW2. Well, I'll admit, the story was a tad bit weaker, and tactics was of the table almost all of the time except three missions(the one where you search for the Oracle, the vaygr outpost with s**tloads of BC's, and the one where you kick Makan's dreadnaught). Except for these, all the rest are pretty straightforward indeed, maybe a bit too much.
However, I kinda enjoyed it being much more fast paced than the first two, and the auto-gather thing is a life saver.
But yes, HW was a lot better story and tactical wise, although I do have my reserves about Cata, will have to go again through it.
As for Nexus, I really have to play it on hard!