No, I find his whole sing and dance number at Val Royeaux fascinating too, in retrospect. "The only destiny here that demands respect is mine," indeed, Lord Seeker Envy.
Makes Barris' hesitation and questioning and finally quiet obedience all the more heartbreaking in retrospect, too, specially after hearing that banter from Denam in the Skyhold prisons where he says "we only wanted to serve, the Lord Seeker seemed so righteous, so certain; everything he said sounded... right." Puts that whole scene and Barris' "our truth changes on the hour" line later in perspective.
I don't actually judge the templars for following the Lord Seeker at Val Royeaux. His line about how he will make the templar order a power that stands alone against the void was most likely the lie he used at the moment to persuade the templars to still follow him, telling them that he will take actions to stop the current crisis such as the breach.
And given that the inquisition is at that point nothing more than a group of upstart rebels and heretics, it's not hard to see why the templars would simply stick to their own, believing that they have better odds at fixing the mess than these newcomers. I don't even judge the templars (especially the rank and file) for not quitting when they finally do arrive at Therinfall, because while their leader's inaction is certainly upsetting and makes room for doubt, one would be forgiven for thinking that perhaps tomorrow will be the day the order is given to march out and deal with the troubles that plagues the land, especially in a military organization where one is most likely trained to trust and obey one superior's orders and not to let ones comrades down by say, deserting them.
None of this excuses the corrupt officers who willfully joined Envy in his conspiracy, such as Denam, of course.
Also, given just how much of a jerkass Envy is at Val Royeaux, it makes kicking his ass in person at Therinfall later so much more satisfying.