I think in the end, the whole issue with the ending is more of a testament to the emotional investment people had in many of the characters and plotlines, which they felt had not enough closure, coupled with bad management and an awkward change of artistic direction.
Personally, I wasn't satisfied when i played it without the EC, and the EC seemed just a huge cop-out that filled the holes but didn't address the main issues, mainly the fact that the idea behind the ending contradicts one of the core principles the other games tried to build up. Synthetics versus organics as a theme was thoroughly denied as a dychotomy all through ME2 and 3, depending on your playstyle, and the ending did not reflect that. Add that the choices were very much irksome (or downright space-magic, as in the sythesis option) and you get an ending that left me, personally, feeling there was no right answer.
Until the very last moment I expected renegade and paragon choices to pop up, like every other time in the thrilogy where a character is being miopic and close minded, and when i ended having to pick i thought "No man should have the authority of controlling the greatest force in the galaxy, so that's the renegade option, destruction is imposing a sacrifice on an innocent populace you have no authority on, and sythesis is just damn weird, but at least i'm the only one dying." and went for synthesis. But i did so just because i had no other option, and even now that they've added the refusal option, a paragon shouldn't pick that, because can't just sacrifice the galaxy because you don't want to choose.
Basically, what i'm saying is that it killed my roleplaying experience. The game up until that point is actually quite good, but knowing i have no option i'm comfortable with that also makes sense makes me weary about the whole thing. If they just had the foresight to exchange synthesis for just "peace" or something, and didn't make it needlessly metaphysical and inconsistent with the otherwise pretty hard sci-fi of the rest of the trilogy, i would've enjoyed it just fine even with the plot holes.
That said, I have no interest in a huge rewrite, the game is still the game and everything else is wishful thinking.
I envy those who played a character that reached the ending and found one that worked for them. Personally, i felt i was suddenly playing the wrong person for the job, and maybe that was the idea. Maybe the point was to underline how the straight and narrow isn't always a tenable position, i don't know, at this point i don't even really care. I don't even begrudge bioware, honestly. It's just a damn pity that my experience wasn't what they planned for in the ending, i've been in form the beginning, i would've loved to be "there" in the end.