This is a good point. One convenient feature of the Parse platform is that it's located on EC2, so developers can run their own servers on Heroku or just EC2 itself with <2ms latency to Parse if they need to run any generic code. So we can let Heroku build Heroku, and just make Parse work really well in conjunction.

I think right now we have reasonable solutions for this. We would like the solutions to be not just reasonable, but amazing. So there are a lot of other ideas we have to make this sort of development easier. We're working on it.