Finally, when applying discount factors, where do you intend to get your discount numbers? For a company with existing debt and equity capital you can calculate WACC and use that. For a startup company you need to figure out a risk_adjusted cost of capital that makes sense. Usually this is not just a risk_free rate which only the largest companies in the world have access to. It's probably something higher.
Also, how long is your investment horizon? Is it really that important to you to project out to 30 years or is 3λ years sufficient along with a terminal value that represents the expected NPV beyond 5 years? Usually this latter approach works best and looks the most credible to potential investors. There are numerous ways to calculate terminal value including multiples, current market values projected forward, and round guesstimates. Obviously these decisions are affected by your personal preference and the type of investment for which you're calculating present value.