I don't believe that a 1 bitcoin per block subsidy forever is necessary to "ensure a strong distributed mining community". I guess you assume that blocks will remain small and transaction fees will remain close to 0 forever. I don't believe either of those.

In what ways to you believe that the strength and distribution of mining depend on the amount of the block reward? In my view, the security of the network depends on the amount of the block reward. High block reward means high security, and vice versa. But I don't know how it could affect the distribution of mining.

Finally, how did you arrive at 1 BTC? Maybe 10 BTC is needed to "ensure a strong distributed mining community". Maybe 0.