M.L. Martin
Hero
To each their own, I suppose. I find the extreme balance obsession in 4e to be very.... scary, I guess is the right word. I'm afraid to touch anything for fear the perfectly balanced mechanism might go spinning madly out of control. 3e I was very comfortable sticking a finger in the wind and saying "Good enough for government work"; with 4e, I feel if I want to come up with a new exploit/spell/prayer I'd better build a spreadsheet and make sure my new ability is not the slightest bit better, or the slightest bit worse, than any existing ability.
This explains some things. It baffles me, but it explains some things.
I felt exactly about 3E exactly the way you feel about 4E. This may be due to not enough actual play and too much reading and following online discussions, but from nearly the beginning, it gave me the impression of 'This is a finely balanced, highly interwoven and coherent system--and we've hidden a lot of the basic assumptions from you. Abandon All Hope, Ye Who Tinker Here." 4E has the same level of rigor in its powers, but at least it's more transparent about the kind of results it thinks you should be getting.
Now, if 3E was transparent or loose enough for you to feel comfortable winging it, then I understand your fondness for it better than I have. I usually felt that if I had to deal with the rigor and detail of 3E, I might as well go with HERO or M&M and at least get the transparency and design flexibility 3E lacked--and I know you can handle HERO, so your passion for 3E puzzled me.

I feel constrained. I find the one-size-fits-all cosmology to be another example of constraint, even if it's only for "official" worlds, it's part of an attitude that has shifted D&D from being a generic toolkit for fantasy gaming to being a set of rules usable only in one fantasy world. It's becoming closer to a setting-based game than a genre-based toolkit, and while I am perfectly capable of (and intend to) using it to do what I want with it, I feel I have to fight the design intent to do so, that the dev team is no longer on "my side", if you follow me.
D&D has always been bipolar in this regard, largely due to the magic system (not just Vancian, but the arcane/divine split and other quirks), monsters, and hidden assumptions discussed above. 1E was a stew, 2E tried to broaden things, 3E seemed to want to have it both ways by both increasing flexibility but undercutting that with hidden assumptions and designing for the 'core D&D experience'. 4E is for 'playing D&D', even moreso than 1E and 3E, IMO.
(And to make my biases clear, I was excited about 4E and think it got a lot of things right, especially in the math, artifacts, and shifting monsters from a 'race-centered' to 'class-centered' style, but I think it's too close to the core experience for someone like me, who's fonder of the outliers.)