I don't think the "nerfs" are bad, as such (though I'll skip on the discussion of futility of "balancing" before getting all the content in place for the sake of brievity, as concerning as I find the practice to be).
What I think is the problem is that there are no new alternatives introduced along with the nerfs. Council of Commons is a good example. Was the influence nerf warranted? Absolutely (though it shouldn't matter at this stage how much influence the player gets, anyway - if anything, it helped testing what little of end-game content there was much faster... AARGH, ok, ok, I stop).
But we didn't get any other means of earning that influence beyond what was already there. And if people relied on CoC, it was precisely because the other reliable sources of it were either very circumstantial (finding and winning enough large-scale battles), or simply insufficient to deal with things like stacked -clan influence kingdom policies.
You shouldn't HAVE to minmax Charm just to participate in kingdom politics as a vassal. It should make it that much easier, but not a requirement - otherwise what's the point of the new skill learning mechanics that, supposedly, should allow you to play as you like?
The game needs expansion of current systems in most places to be enjoyable and truly open sandbox. The resulting player experience after the various nerfs merely highlight that need.
And this goes right back to the "balancing before expanded content" argument.