Unit customization is not a natural fit for a strategy game, particularly not a 4X game where research and economic infrastructure are the chief drivers of military progress.

We don't even know where to start.

Armor bone is connected to the hip bone, flak cannon is connected to the shoulder bone...

Customize all you want, but your battleship should still be a heavily armored slugger, and your cruisers should unleash a torrent of gunfire.

Fodder fodder everywhere.

Whenever I see a strategy game touting the fact that I will be able to design and build my own custom units, I enjoy a flicker of hope that this time, maybe, unit customization will add something exciting. Then I remember Ascendancy, Alpha Centauri, Elemental: War of Magic, Sword of the Stars 2, Gratuitous Tank Battles, Endless Space, and a dozen other half-forgotten sci-fi strategy games that thought I cared how many Whocaresitron guns my space ships carried, and whether they could penetrate Adadurasteeltanium armor. I cannot think of another feature with such a mixed track record that enjoys such enduring popularity among gamers and developers. While customization might be fun for tinkerers, strategy games aren't Lego, and customization brings complications that may not translate to greater depth.The main problem is that unit customization is not a natural fit for a strategy game, particularly not a 4X game where research and economic infrastructure are the chief drivers of military progress. When you play a game like Alpha Centauri, for instance, there is a fairly narrow band of weapons and armors that you can employ in battle. If you are using weapons that are more than a step or two behind the current cutting edge, the exact unit specifications don't matter. Units simply will not have the firepower to make a successful attack. If their armor is a step or two behind the standard, it can't survive an attack. Unit customization ends up being this ritual where you confirm your technological progress by updating the specs on a few basic unit templates: garrison units, artillery, tanks, fighter-bombers, etc. It's kind of like an RPG: you level up and your stats improve and you get some new loot, but nothing really changes because all the enemies advance so that you have the same relative relationship.To a greater or lesser extent, this same dynamic is at work in most 4X games. It doesn't make customization meaningless, but it does marginalize customization's impact. Loading an extra pair of lasers at the expense of a bit of armor plating isn't going to make much difference compared to having a couple more research labs and factories. In fact, I even get a little annoyed when I have to spend an hour drawing up new unit specifications when all I really want are units that fulfill simple tactical roles. The question of how to make a unit fulfill that role is not a question I play strategy games in order to answer.Consider what happens when the focus changes, however. Any BattleTech game, like MechWarrior or Mech Commander, is also driven by customization. X-COM: UFO Defense and Jagged Alliance 2 are as much about what your soldiers are carrying as what you do with them once the shots start to fly. But these games are 90% about battles and tactics. Customization and loadouts are hugely important here because I want squads and lances that are appropriate for the battlefield and allow me to execute the tactics I prefer. Besides which, obsolescence doesn't make the majority of my options irrelevant at any given time. A shotgun in the hands of an assault trooper still has a role to play in some circumstances, and a BattleTech game still gives me reasons to employ lasers, despite the fact that Gauss rifles do more damage.The other problem with customization is it throws open a huge menu of options, but it's by no means certain that players will have the context to make smart decisions about the units they build. It creates an entirely avoidable learning-curve issue. If a game gives me units called "Siege Artillery" or "Interceptor," I have a pretty good idea of what those will do and how to use them. If it gives me a blank chassis and a bunch of cryptic-sounding pieces of equipment, each with its own stats, I'm at a loss.Endless Space is clever about how it solves these problems, but the solutions are also revealing about why customization tends to be unsatisfying. It gives you several different types of ships, and each has stat modifiers that allow it to carry particular types of equipment at a lower cost than normal. So battleships can add more armor without going over their weight limit, corvettes carry support equipment like repair modules and long-range sensors, and cruisers can carry extra weaponry. It's not a bad approach, but it also slaps the player upside the head and says, "This is what this ship is for, dummy!" Customize all you want, but your battleship should still be a heavily armored slugger, and your cruisers should unleash a torrent of gunfire. It is a tacit admission that there is a "right" way to build these units, and customization is really just a way to tinker at the margins. Furthermore, once you've designed a ship, it's very easy to click "auto-upgrade" to make sure the same basic design persists through several generations of technology. Because, again, tech is what matters, not loadouts. Endless Space just does us the courtesy of acknowledging this.But my real problem isn't with customization itself. It's the way it's so often treated like a condiment. It's not easy to make customization fun and exciting even when it's the overwhelming focus of the game, like in Gratuitous Tank Battles. It's even harder to offer a rewarding, challenging customization system on top of a fully featured 4X strategy game.So by all means, let's have games that let us custom-build units and set our mechanical creations against our enemies.' But let's make those games be about custom-built units and learning to use them in conjunction with each other, and leave all the Civilization trappings aside. I don't need every game to span the galaxy or the globe. I just need them to get their arms around their own big ideas.: Everything is better when it's customized! For example, you don't think this green fedora was bought off the shelf, do you? What's the best custom unit you've ever made in a game?