My biggest criticism against the Wardens is their secrecy. For example, if you are going to lock away a darkspawn Magister in a magical prison that no one can escape from, then you should at least warn people to keep away and remember to keep guarding it. They must have had records back at HQ that detailed the reason why they had imprisoned Corypheus instead of killing him. When word got back that he was no longer there, alarm bells should have started ringing and they should have let everyone know what the problem with him was. They knew he could influence mages but particularly Warden mages, regardless of the false calling, which could have come totally out of the blue.
However, I always felt the Warden decision was misleading. First play through my girl was heavily influenced by Solas and banished them but even she thought this was only going to be temporary and I specifically told Leliana not to put the boot in and rubbish them with the rest of Thedas. Yet at the end, I discover everyone is turning them away because of what we did. This is not what I intended. I was sending them away for their own safety as much as anything else but once Corypheus was dead, they were welcome to return. This was not reflected in the game and everything concerning the banishment was negative.
By contrast, if you keep the Wardens there are no negative consequences. You get extra war table missions and the supposed risk from Corypheus never materialises. At the end the Wardens are not only still with the Inquisition and in Orlais but actively working with everyone throughout Thedas.
This is why the latest decision concerning the Inquisition has me wary. It is meant to be a trade off between great strength but risk of corruption against weaker group but totally secure so no infiltration from outside agents. Since intelligence and secrecy are likely to be the best weapons we have in hunting down Solas I'm hoping that if this decision has any bearing on the next game, this trade off will be properly reflected. I'll not be best pleased if they make working for the Divine the best option with the potential downside of corruption ignored like it was for the Wardens, whilst the outcome for the opposite decision is wholly negative.