Out of curiosity, why can't all of the calendar templates have the same settings and options for grouping? I know that you guys design each template to offer a unique look and for it to be different that the others and that is great, but maybe not really necessary. If all of the templates had the same options for grouping, defined fields and other settings, there would be less problems for users who like something about the Performance template, but don't like that you can't group things like the list template.
The different templates are great for getting a different appearance. Each template is designed to look different, wonderful for those of us who have different needs and want them to look a certain way based on what we use them for. However, I believe the functionality of the templates should not be different; but the flexibility to modify them, such as adding a defined field or defining the order of the fields is a way of altering them for each users preferences.