Very good post. I know I can at times be one of these change fearers but I try not to be. Though the two things you mentioned Scion and Thieves both changed drastically from the time they got implemented to now, where people are happier with them. As for talking about Scion after it's complete revamp, I think I like most people had no idea it got a revamp to explain things better and give it a purpose so the complaints kept coming. As for thieves I tried a poisoner a few months after it came out and it was just broken. I complained on the thief board and largely got ignored, now I see alot of the things I complained about back then finally got fixed(even though at the time I was told by design).
I can tell you wrote this in some part to head off the mounting complaints about Outlander. I'm sure there is a lot of time and thought put into creating Outlander and things we as players don't realize yet are factors. I also think though that you can't truly see how something is going to work until it's put into practice. For example while you guys might have decided that manacles is really no big deal for outlander spell casters, in practice it's a huge draw back for them. While I'm going to try to stop making any rush to judgements on the cabal now(Already made a few), I definately think it's like Scion when it first came in. In time it's going to need polish on it's RP/Story and a definate look at how well the powers fit the new cabal. I'm hoping this comes soon as opposed to later.

That which does not kill us,
makes us stronger.