The new runtime sounds extremely great, and basically, it's almost all that I was really hoping for. I don't mind the subscription model, and actually, the web-based system is quite practical when I can access my projects from anywhere. If even half of the features that are spoken of are provided, then C3 is more than justified.
Some Features that I'm hyped about:
1. Improved performance
2. Modular events
4. A more capable graphics system --> e.g. official drawing canvas
I have used most of the common game engines, and none of them are as fun and snap to use as C3. And if the new runtime redeems all the promises, the only missing thing is console exports (PS4, Switch). At the moment C3 is great, but it's going to be kick-ass epic!
Scirra is definitely ahead of their time with C3, and I can see more companies follow the same path in the near future, but I just hope that Scirra hasn't lost too many of the evangelists and important stakeholders with their business direction. I have seen the frustration and leaving of the more serious game and add-on creators, and it's probably impossible to win them back, even thou C3 would be everything they hoped.