I don't play any competitive StarCraft so my view might be moot but I was surprised at the number of siege tanks it uses. It made me wonder if there's some critical advantage to having so many tanks stacked up in a line so that the splash is spread out.
Also I find it weird that it did not build any marauders at all, in any of the games I've seen.
And just in general, no sexy units. No battlecruisers, no infestors, no swarm hosts...