The preferences tab in my user profile here looks like the following.
There is a single, actual preference in there, the option to hide ignored tags entirely, and a whole lot of whitespace. The favorite tags are already accessible in a much more convenient and discoverable place in your sidebar, they are entirely redundant here in the preferences.
We all know SE hates preferences, so let's get rid of the whole preferences tab entirely. The favorite/ignored tab is redundant anyway, and the option "hide ignored tags" would fit nicely on the favorite/ignore tags section in the sidebar. At the current place, nobody finds the bloody checkbox anyway if they're not told exactly where to look, moving it to the actual favorite/ignore tag UI would make it vastly more discoverable and is a much more logical place for it.