Purely a personal opinion, and I appreciate it would need a serious change in governance, but I reckon the DHF and witness rewards could be used as a mechanism to burn enough HIVE to create a deflationary effect.

I believe the DHF should primarily be a loan rather than a grant mechanism, and that any DHF funds given or lent could be matched by burning an equal quantity of the DHF's reserve of HIVE.

Likewise, if witness rewards were matched 1 for 1 by burned HIVE, it would be a way to burn a mathematically calculated number. Although I also think the witness rewards should be on more of a gradually decreasing sliding scale rather than a sharp cliff after the top 20, and should be more correlated to the levels of Hive activity, which would provide us far better ability to scale growth to activity.