I'm happy you took the non-coding approach, it will be much easier for the analytics or marketing team that won't have to wait for the engineers to push changes to the tracking code.
I didn't find it on the website so I'll ask here: Do you do like heap and track all user interactions and then allow to track whatever you need on the fly, event past events?
Hope you take the same approach on the web version. It's the only pain point I see on Mixpanel.
Thx, and keep up the great work, I use MixPanel a lot :)