It should be noted that theoretically there is a bug in my rewarding mechanism: if all miners unite to form as many blocks as they can on top of one single block, and after 4 months or so include all blocks' headers within a single block, then they might be rewarded more money than the total sum of taxes (i.e. making the Bitcoin Security Reserve in overdraft).
This obviously is really unlikely, yet if someone is nevertheless interested in a solution, we can simply limit the number of block headers included in a single block to be at most 10 for say