You're correct that my immediate tests are all at the lowest level of abstraction. I picked them simply because they are the types of distortions which manifest first and quickest and least ambiguously. If you or anyone else isn't sure if the acid has kicked in, or is uncertain that they are experiencing any changes, these are the debugging tools. At higher levels of abstraction you get things like streamers, transposing of near identical objects, and sometimes even weird face distortions.
The taste thing is quite curious to me. Have you considered setting up an experiment to try and pin down exactly which flavors are distorted and how?