I wanna take you for a ride
The very chaotic nature of Champions game system is that it will either be ridiculous and overpowered or boring and homogeneous. With so many powers and different ways to make a character, those are really the only two options. History has shown us that games with this many options are inevitably unbalanced, because even in the case of games where most of the options are roughly the same, a few options, powers, or abilities tend to be "mostly the same as others, only slightly better."
In general, the "ridiculous and overpowered" approach tends to make for more fun games, even if game balance is sacrificed some in the process. If we look at box sales, games with a truly varied and original cast tend to sell better, even if those games aren't perfectly balanced.
While I'm not saying that deliberate imbalance is a good thing, trying too hard to balance things makes everything too similar. It takes a bit of lateral thinking to make a balanced game. More than that, it takes time. Often small changes have ripple effects in the meta, and it takes a while for people to figure out what to do with them. Modern competitive games take years of study to learn. Champions Online is no different; it simply has too many different interactions for players to just "figure out."
On the same token though, developers have an even more difficult time. There simply aren't enough developers for any game to test every possible interaction, and it's well known that players who discover tricks or exploits tend to hide them in order to preserve an advantage over other players.
A new age of MMOs
Champions Online's greatest selling point is its open character customization. Although cosmetics are the most commonly touted reason, CO really shines because you can combine cosmetic modifications with a varied set of powers to create a truly unique character. In World of Warcraft, you can define your character in two words; "prot warrior" or "affliction warlock." It's both a blessing and a curse that players generally cannot do this in CO.
If one takes a concept as basic as "Might tank," it's easy to get confused, for instance. The player might be using Might for his damage powers, but be using Invulnerability as their passive, rather than the Might passive Defiance. Referring to a character as an "Invul tank" is even more troublesome, as an Invul tank might be using ranged powers to get or hold aggro. He or she might also not even have Constitution as a superstat, instead favoring Presence for better self heals and more threat. A typical description might be "Defiance tank with mostly Might, but uses Gigabolt for grabbing aggro." Even that doesn't cover the possibility of Enrage or self-heal powers.
If you read the above paragraph, you realize how many different functions a character can have. A whopping four powers and two stats were mentioned, and the presence or not of those powers dramatically change what kind of character we are talking about. If you play CO, you might take this for granted a little, but this much diversity commands a little respect.
There are a few hundred different powers in Champions Online, and a hero can select 14 of them (and two travel powers). Although there are restrictions from selecting higher tier powers, the number of possible power combinations range in the millions. That number is so big that our brains have trouble contemplating the depth of it. We can compute hundreds of possible options with difficulty, but millions? This doesn't even include stats or advantage spending!
Here comes a new challenger!
I know what argument comes next. We don't have to think about a lot of those options. Some of those options are so ridiculously similar that it doesn't matter, right? A lot of those builds are so bad, that we shouldn't even acknowledge them (picking 12 to 13 tier 0 powers for instance).
This, ladies and gentlemen, is my point. Champions Online isn't balanced. Even if we consider the relatively practical builds, of which there are probably hundreds of thousands, there is a huge difference in performance between builds designed to do roughly the same thing.
This is not really a bad thing. In the epic battle of "balance versus diversity," one side has to give. CO's main strength is in the uniqueness of each character. We already have something like a dozen powers (tier 0 blasts) that literally have the same function with very minor differences, and these powers are boring. There's a reason why no player takes more than one and most PVE players try to avoid them at all costs. I want powers that are fun and creative and allow players to express themselves through both the visual power effects and the actual power mechanics. That's why I play Champions.
The developers can't just ignore balance entirely, but I think that more attention needs to be spent looking at the powers that nobody likes (like pets and tier 0 blasts) and focusing on making those fun and unique as well. If some really abusive powers need to be reduced so that the game can be more fun as a whole, that's obviously fine, too.
Some games rely on meticulously crafted balance in order to create an enjoyable gameplay experience. Other games are fun just because the designers decided to go nuts and make a fun game.
Go nuts, guys.