Keep in mind that members may post at different frequencies, and decisions you make around that will make it more (or less) attractive for different demographics. The worst possible setup will be for the upvote per post to be exactly the same for everyone, with no limitation on frequency. @qurator limits upvote frequency to once daily, @steembasicincome adjust upvote value based on post frequency and upvotes every post (except for in pool 7). I'm less familiar with @make-a-whale, but it looks like they also rate-limit to once daily.

Of course with once daily, your core demographic is people who post at least once per day. As you pointed at correctly about SBI, the people that don't post help boost the returns for those who do, but we calculate on a weekly frequency. If you calculate on a daily frequency, then it is exacerbated even further, with people who may post only a couple of times a week incidentally passing their benefits to people that post every day. At your price points, you will likely only attract people that post every day. Would be interesting to see how the actual vote compares to a similar level of investment in SBI, but there isn't enough information here to do that.

I do like the solution you came up with for growth dilution, as there are some limitations to the solution we came up with (as seen by the fact that our target multiplier has dropped over time). We considered that, but we wanted to keep SBI accessible to everyone, even in a rising STEEM price regime.

Good luck with your project, and let us know if you want to discuss any of the points, since we do have a little experience here.