There isn't really anything "precarious" about TBN's balancing other than the fact that its balance is closely tied to a number of other skills (Dark Arts, Bloodspiller, and the entire Souleater combo) that, realistically, should all be adjusted together every time any one of them is adjusted, which SE is not doing.

There aren't really any huge fundamental changes required; ultimately the issue is just that fine-tuning on skill balance happens in updates that are months apart when the situation really calls for more of a week-to-week approach.