xx see AG comments on what’s below. Ultimately, we need a short list of standard comparisons, such as:
For visual comparison of time series data, we have two main options, the so-called small multiples and animations. In case of small multiples, showing too many of them could be a problem. If it will be an animation (or several animations), all dynamic visual variables should be considered for accurate recall. There are also various illusions with animations, e.g. brain tends to fill in the missing frames (apparent motion).
For comparison and/or predictions; representing uncertainty may be especially important: the two compared phenomenon (visualization?) may have different sampling rates, different model precisions, different processes. Try to make sure you are not comparing apples to oranges and make sure that the fact that one is an apple and the other is an orange is explicitly stated in your visualization.