Thanks! Totally appreciate the concern about the longevity of a new tool, I feel the same when I find something new.

We're working on Pro at the moment which will have a more full feature set for organising and editing/updating/sharing charts.

About traction, we're a VC backed startup and we've been working on our mission to give people data super powers for a couple of years. So at the very least, I can say it's not a side-project that will get forgotten about!