I feel like I'm one of the few people who really enjoyed the Ori arc, though. For the first time in several seasons I felt as if the Earth was truly in danger, because not even the Asgard could beat them initially. Did I feel like the sudden resolution with the Asgard developing and giving new technology to the humans as sort of a cop out? Sure, as did pretty much everyone, because it essentially gave the humans a ridiculous advantage against every foe, even the Wraith (except of course the superhive). I also think the Ark of Truth being found so quickly as sort of a cop out as well. I'm sure if the creators had had a whole season given to them to wrap up the series it would have been better, perhaps wrapping with a three part finale to the Ori arc.
I enjoyed the Ori arc, as I said above, but I will always feel like they defeated them far too quickly given that the Ori were far and away more powerful than the Goa'uld.