When writing about Warcraft 3 I have always tried to avoid subjects where the conclusion gets colored by my own opinion. I have done this by writing guides, tournament reports, etc.; subjects where there, more or less, is one objective truth. Now I will try to open the door for writing more opinionated articles (op-eds) as well.
The reason I mention this is because it is important for me to clarify that this type of articles' purpose is not to lecture you, the readers, on how and why you should care about a subject. Rather, its purpose is to get you interested in what I find to be important issues, as well as encouraging healthy discussion about said subjects with the right balance of thoughtful analysis and facts.
So in short: You are allowed to disagree all you want, but let us strive to have a civil and healthy discussion about it!
Undead is notoriously known for being the race with the least flexible game plan. Achieving a fast tier 3 and getting your core units, Crypt Fiends, Obsidian Statues and Destroyers, topped with an Orb of Corruption, is simply the way to go. Against all races.
Though other races also have their core units, their hands are simply much less tied in regards to being creative. Orc is a good example. They also rely heavily on a few certain units in most matchups: Raiders and Spirit Walkers. Yet they can also opt for mass Raiders/Wind Riders, staying tier 2, together with having a lot more space for trying different hero combinations.
This brings me to my next point: How Slaughterhouse is hindering Undead. Slaughterhouse is obviously not a hindrance because it is weak, but I think it plays a big role in hindering the Undead race of becoming more flexible. Right now they simply have everything they need in the Slaughterhouse (and Crypt), ergo rendering Temple of the Damned and Boneyard obsolete. Because even though units like Abominations and Meat Wagons are not considered a core in the standard Undead army, it is still vital to have them easily accessible as tech units.
Slaughterhouse is the only tier 2 structure you need to cover all your army's needs. It is true that there are other units that serve niché purposes, like Banshees for Curse against Orc and Anti-Magic Shield against Undead, or Frost Wyrms against Night Elf bears, but these are units that compliment an already well-rounded army. They are a nice luxury to have, but they do not cover any essential gaps - cherry to your ice cream.
infi doesn't care about what's 'viable'
Solving the issue of Undead not having much flexibility is complicated. We saw that Blizzard attempted a flexibility fix by buffing Necromancers and making it easier for Undead to expand. Unfortunately after a few weeks the general game plan reverted back to what it has been like for years.
The most interesting suggestion I have heard is to move Obsidian Statues from the Slaughterhouse to the Temple of the Damned. This would spread the key army components into separate tier 2 structures, thus not throwing Temple of the Damned out in the cold. It would also fit well with having the utility-based caster units in one structure.
I do, however, not think the solution is that straight forward. It would be a too hefty nerf for Undead. Something like a tier 2 Riflemen push would be very awkward to deal with as you are forced to put your eggs in several baskets.
So, do I have the perfect solution for the problem? No, unfortunately not. I do not even think there is an elegant solution. My best bet right off the bat would be to move Obsidian Statues to Temple of the Damned and reduce the research time of their morphing ability by a substantial amount, but that is still an iffy idea for several reasons.
Do you agree that Undead could use more flexibility in their play style? How would you make Undead more flexible? Do not be afraid to voice your ideas even if they are a bit out there!