> I prefer checkpoints to an inflationary hard fork.
I don’t know what you mean by “checkpoints”.
One other option nobody ever mentions: increasing the block time. If the block time were to increase on a schedule like the halvening, then the block subsidy would never run out.
Increasing the block time can be achieved by a soft fork. Legacy nodes would simply see blocks coming in too slowly and continue to ratchet the difficulty level down, while upgraded nodes increased required difficulty per the increased block time.
Such a change would have the added benefit of eventually unlocking the possibility of mining elsewhere in the Solar system. The current 10-minute time is too short for Martian miners to reliably receive terrestrial blocks, for example.