At what point were characters the most powerful?

[mezzosoprano]

When in the game's lifespan do you think that characters in CoH/CoV were at their peak power?

For my Plant/Storm Controller (one of my favorite characters), the peak was the period where the Reactive Proc could proc from pets and DoTs, stacking a near-infinite number of times.  I could run ambush-mechanic-abusing AE arcs and decimate a ridiculous number of enemies as Freezing Rain, Roots, Carrion Creepers, Lightning Storm, Ice Storm, and Tornado all wreaked havoc.  With the T4 variant, I was earning nearly 3M inf/minute on my controller, with the Reactive Proc generating nearly 70% of my total damage.

I had a great time confusing people looking for tank-led PL teams -- "Aren't you going to wait for the tank?"  "What tank?"   :)

[Advanced]

My Stone/SS tank had some problems after ED, it was not the same. However; with a little bit of math I was able to fix his problems. Invuls got hit hard unfortunately (glad I never had one). My Rad/Elec defender got better after ED, he was finally able to dual Dark/... Defenders in the area. ED I think diversified the game more, and made people have to actually think about how they wanted to slot their characters. Was I stronger pre-ED? No doubt (Remember Regens tanking Hami solo like?), but did I become a better player after ED? Hell ya, how else would I survive the devastation. At times, the game got a bit scarier after ED. Hahaha!

[MWRuger]

I think a more useful question might be when were they more fun to play?

Of course everyone has his/her own view, but was a there a level range were the challenges were well balanced versus capability and you had enough powers to have varied strategies for dealing with those challenges?

For me, I loved it at just about every stage, but if I'm honest it always really gelled for me in the 30's.

[Canine]

For me, I loved it at just about every stage, but if I'm honest it always really gelled for me in the 30's.

22 was when characters started to become more fun to play for the vast majority of my time in the game.

Stamina, 3 slotted with +3 SO's.

It became less about dementedly managing the blue bar to being able to concentrate more on the other things going on.

[Ankhammon]

22 was when characters started to become more fun to play for the vast majority of my time in the game.

Stamina, 3 slotted with +3 SO's.

It became less about dementedly managing the blue bar to being able to concentrate more on the other things going on.

Well, if we're talking about level your personal chars got better it has to be level 12. DOs weren't anything to write home about but level 11 was the worst. No n00b buffs and just some nasty level 10++ TOs (usually all acc at that level) to try to make it through just when you started to take on something that could hit back a little.
To make things worse, if you had a team going they usually broke up right about that level. 

It always felt like xmas when I dinged level 12 and could go shopping for an end redux to add to your acc's in your attacks.

[Waffles]

Let's not forget that glorious....GLORIOUS knockback > Knockdown enhancement.