I'm so humbled that this investor was willing to take a risk on us, our product, and our vision that I'm confronting a threshold question in my first relationship with an investor:
Do I send him a personal gift to convey my deep appreciation, or do I just stay focused on the product and pretend like I've been here before?
I would just say what you did here, you're really appreciate of their confidence in your company and product, and look forward to the future.