I full well understand the logic behind The Events Calendar (I'll use TEC for short) using the WP-maintained postmeta table; after all, TEC essentially uses "posts" to create / maintain events. It's not at all illogical, and I see the point of doing it that way. However, I believe there's an inherent problem with using the postmeta table: vulnerability, and (arguably) structural integrity of the content tree.
So, my question / request for consideration is to look at the possibility of using separate table(s) for TEC.
This has an additional, tangential benefit of allowing for a more straightforward conversion of data / events created with other calendaring plugins that use their own table(s) as well.
Getting back to the argument of using a separate table: by linking posts to events, I believe the fundamental semantic distinction between the two is better preserved, e.g. allowing for inclusion of multiple references (i.e. in different posts / pages) to the same event, making an event therefor a separate and distinct "data category" (for lack of a better description) akin to media, links etc.
Bit of a philosophical issue this, and I full well realize the implication of even momentarily considering this suggestion (i.e. a lot of recoding!) but... There it is. :-)