In the case of RethinkDB I wish they had started Horizon much sooner. Having plugins like for Stripe will make Horizon usable in the real world. I certainly like the goal set for Horizon that it be easy to extend a Horizon app by embedding it in a Node app. I just found the lack of step by step tutorial and several examples frustrating.
I've just started learning about business stuff. I've gone to three Seattle Lean Startup events. I've learned a lot. Two key things I've learned that are helping me are make a working engine before raising money so that money is just gas and focus on making something that people pay for.
Being involved in SMC I'm very glad that VC hasn't been taken. I'm not convinced that VC would make things much better.