I can't see any features listed that enable me to control costs to prevent surprise bills. If a site got submitted to HN and hugged to not-to-death-because-it-autoscales then I'd wake up to a bunch of alerts and massive outbound bandwidth bill. I don't want that. I want something that stops that happening.
If the App Platform doesn't have that feature, and it isn't planned, that's OK but I'd argue that isn't really preventing a surprise bill as the marketing site claims. A warning isn't quite the same as prevention.
This is exactly the sort of thing I'm talking about, but for money rather than computing resources or bandwidth. I'd like a feature that where the requirement is effectively "Fall back to a serving sorry-I'm-poor.html instead of the app if the total monthly bill has exceeded $xxx". For a side project I'm more interested in not paying an unexpected bill than getting traffic.
You deposit funds (let's say $20) into your account, and as your site consumes resources, it draws from your balance. So $20 is $20. If you set up a crummy low-traffic blog and that $20 lasts four months, then fine. If it lasts two weeks and then there's a surge in traffic, or the server hits some bug that causes it to spiral out of control, then your site gets killed when your balance hits $0. You can set up alerts, but there's a hard limit for how much you can be charged—it's whatever funds you deposited into your account. (Really, that's not even the right way to put it, because you're charged at the moment you deposit them.)
This isn't acceptable for everybody—many businesses would prefer to stay up and be billed after-the-fact. But that use cases is already well-served by the industry. (Overserved, really.) The market segment where the alternative situation is the best fit (pretty much every hobbiest who isn't bringing in a single cent off their side project) is extremely underserved. NFSN is the only provider I know of that even offers this.