I understand the skepticism, to be honest I was also pretty skeptical when we started (I am still a little bit, a healthy dose :D!), but we think now we can get to the level of flexibility of serious web frameworks - it all comes down to figuring out where the flexibility is needed.
Right now it is already pretty flexible - you can write any nodeJS logic and use any JS library, same goes for React components. What is tricky is hitting this right trade-off between flexibility and power, and we are thinking a lot about that.
So to summarize, I agree, but am hopeful!
e2e testing -> yes, that would be very cool :)! We don't have any testing capabilities yet, but will be looking into it.
Regarding bigger projects - one thing I am excited about is the possibility to model not just one web app via the DSL, but to capture multiple services - for example multiple (micro)servers - and orchestrate them. I haven't explored that direction enough yet though, since it is not the priority right now.