The blue is slightly too vibrant also. You want to be careful about the saturation of your colors. Vibrant/Saturated colors are subconsciously distracting and unprofessional.
This is completely subjective though. To me, for instance, We Pay's current webpage looks like a site I might use for the scenarios described in the NYT article, like a way to collect payment among a group of friends. Your mock-up looks like the site of a bank or mutual fund, which is exactly not the sort of site that comes to mind for the purpose. Again, this is completely subjective - I just don't think there is any way to justify something as vague as 'vibrant is unprofessional'.
This is completely subjective though. To me, for instance, We Pay's current webpage looks like a site I might use for the scenarios described in the NYT article, like a way to collect payment among a group of friends. Your mock-up looks like the site of a bank or mutual fund, which is exactly not the sort of site that comes to mind for the purpose. Again, this is completely subjective - I just don't think there is any way to justify something as vague as 'vibrant is unprofessional'.