Predefining rigid milestones can be overly limiting to the flexibility of the project, which is critical to survive in a dynamic environment. If you take cues from what’s served VC for decades, a multi-stage release of tokens rather than a single giant ICO probably makes the most sense. Eg. bake in future secondary offerings of N% more on top of the ICO and obviously they’ll be market-driven based on what the market believes the team has achieved or will achieve.
Not likely in the current environment (why bother?) but I suspect we’ll move there.