Sorry to have annoyed you, but there's really no better way to gauge interest/insight into what your doing early than this type of approach, it really does work out for the better in the long run.
Thats exactly what your call to action says.. but thats blatantly a lie.. It gives the expectation of instant access.
"Sign up to learn more, Coming Soon, Be the first to know"
all alternative CTA's that are less deceitful.
https://chrome.google.com/webstore/detail/deejobgbijaihniifc...
It uses html/css, so you can even edit the things you import.
I got so excited, signed up, and then nothing :(
That said, as a designer myself the Scratchpad process is largely based on an existing process I've employed for a while to get things going to show other's in a simple manner what i'm thinking and get early buy in to be able to move forward faster and on my own terms.
Instead of taking the negative route, you could just tweet about it and ask for early access...
Exciting service. I would still be giving my email if it said "be the first to know".