There has been a lot of complaining about balance lately. Some of it even came from this blog. However, all complaints about balance come down to one idea: something in the game is too powerful. This is a wrong way to think. It is my opinion that nothing can be too powerful.
I'll stop for a second to let you clean up the drink you just spat out.
Nothing? Nothing. Not even an invincible model that has a weapon that kills every model within 24" and cannot be removed from play, even by effects that instantly kill everything? Even that. Here's why. It's a nitpicky stupid way to look at it, but I think it works. Nothing is too powerful AS LONG AS YOU PAY THE POINTS FOR IT.
Which begs the question: what IS a point? How do you determine how much a model SHOULD cost? Chances are, you've heard another gamer say "Man (insert unit name here) should totally cost (insert integer here) more points per model." But how did that person come up with that number?
Well, lots of people just make them up. However after being thrashed by Nob Bikers/Missile Wolves/Flying Circus/Whatever enough times, you figure out just how many points on average that unit kills. You then compare that to the actual cost of the unit. On average they should be the same, and if the one is higher (usually MUCH higher in the cases where this much complaining happens) then the unit doesn't cost enough and is "overpowered."
But this doesn't answer the question. What IS a point? It is a mathematical representation of simulated military power. Because it has a fixed value (multiples of one, you can't have half a point) then ideally on average a unit will "make its points back" plus or minus a bit. It's those units that make WAY more than their points back on average that are overpowered or underpointed.
Sadly, once identified there's not a really good way to fix the problem without an errata from the game company, which are sometimes rare (GW has been good lately, bringing Dark Angels and Black Templars back up to par).