I like this concept a ton- I tried to sign up and it to me to another page that was blank. Would love to try it whenever you get the initial issues worked out.
I would say a yearly raise keeping up with cost of living/inflation would be expected. That's about 3-4% per year. I've grown quite a bit in my current gig, so I asked for a 10% raise this year and got it. I would say that is fair.