For now it's going to be on-prem, so each user will just have their own cluster. Things like E2E encryption are pretty easy to implement on top of Rama's existing primitives (there was a good question about this on the rama-user group yesterday https://groups.google.com/u/1/g/rama-user/c/jj-ILcoMjtk).

We'll likely have a fully managed cloud version in the future.

Riak was good technology at the time, but it was really hard to distinguish from other K/V databases and didn't really move the needle on core business metrics (like development cost). Rama dramatically changes the economics of building large-scale software. It will take awhile for many to grasp that, as is obvious from many of the comments here, but I expect that as more and more users have massive success with Rama, that understanding will come.