Aw, you had to go and sound all reasonable! Dude, this is the comments section. You're supposed to just call me a retard and pledge never to come back!
I think your mistake -- maybe "mistake" is too harsh a word, but I feel strongly about this on a philosophical level -- is assuming that more words are somehow more valuable.
I can absolutely talk in more detail about the role of the different units, and I've done so elsewhere in this comments section. But I don't feel that a longer review is necessarily a better review. When I write a review, my goal isn't to spell out the details. My goal is to inform, raise questions, and entertain, often in that order. And brevity can be an important part of that. The economy of words is an important principle for a writer and one I wish more game reviewers understood.
But if someone wants more information, well, here I am. We also have a thriving forum that I participate in. And if that's not enough for you, I do a weekly gaming podcast (our last episode was about how casual players approach Starcraft II).
Also, you're reading too much into my comment about the "overall picture". I thought it was clear from the context that I'm talking about balance issues and how all the pieces fit with each other. As I said, I trust Blizzard. I know the new units went through a lengthy beta process. I'm not being dismissive about the units because they don't belong or they're poorly designed. But I am aware that they're not units I feel the need to use, so this isn't really an add-on for me. It affects my experience with Heart of the Swarm when I look at the spawn host and viper and think, "Well, I'm probably never going to use those with any degree of efficiency..."
Furthermore, like most players, I play a single race. I'm happy to dabble with the other races and I did so for this review. But I don't pretend to understand the other races as well as I do the zerg, at least from behind their own hatcheries, which -- for some odd reason -- aren't even called hatcheries! What's up with that? Nexus? Command center?
Like almost everyone else who plays Starcraft II, I'm not qualified to make judgments about its balance. That's a complex issue and you should regard with skepticism anyone who holds forth about it, particularly if they're speaking from personal anecdotes instead of data. Just go to the Blizzard forums for all sorts of useless pronouncements about balance. I have no desire to add to that noise when I'd just as soon take it on faith that Blizzard knows what they're doing.