My first thought is that “it would be nice” to be able to store desired Core Settings and UI Preferences for my account. However, it isn’t necessary. I think that the annoyance factor of having to change settings each time is minor.
Unrelated tangent: I do feel strongly that default settings should exist at some point, either per-user or site-wide. It is a nice sentiment to say that, for example, we shouldn’t make assumptions about whether the user wants metric or imperial units or favor one over the other by setting one as the default. However, at the end of the day, the UI needs to start with some default behavior for the sake of consistency. Removing default settings and instead having the UI start with no settings at all seem to have resulted in a number of bugs and inconsistent behavior.