I see no evidence that those 1000 signups can be attributed to your pretty design. In fact, I dare say you held the belief that design was important long before

I see no evidence that those 1000 signups can be attributed to your pretty design. In fact, I dare say you held the belief that design was important long before the product release, which is why you invested your time in it. Perhaps it was the particular domain or the viral marketing. Conclusions without evidence is just conjecture and supposition.