It seems like Bitcoin’s inflation rate should be one of the parameters in determining the target block reward but far from the only one. The biggest consideration, in my opinion, should be the security of the network (i.e. how do we ensure the likelihood of 51% attacks remains low, how do we keep a diverse set of miners on the network, etc.). I think a section describing this in details would help with your rationale.
My hunch is this is much too dramatic of a change, given we’ve gone from 5 to 3 (-40%), then 3 to 2 (-33%), now you are going from 2 to 0.5 (-75%). What justifies increasing the rate at which block rewards get diminished vs. decreasing it (for example, to -25% which gives us 2 → 1.5)? Again, I would personally like to see some security analysis that supports the numbers.