This isn’t really a color picker but it is a very useable resource.
Testing web design is challenging, nut-cracking and back breaking! Here’s a rundown of current practice.
There are a lot of color scheme pickers out there. Which do you think is the best?
paletton.com allows for some very subtle nuancing.
Some other ones:
Here’s a very useful article about the process for designing a logo for a company. Notice how he didn’t just open up Illustrator or Photoshop and start designing. First he gathered information via a questionnaire (interview) from the client.