Hello,
The proposal you suggest makes sense, however it would need a large number of changes to the code, some of which can introduce problems if not done carefully. I have not yet performed an initial analysis of how hard it would be, so I can’t comment on that yet. I will have to work on it first, to determine what needs to change and how long it will take. I am scheduling this change and I will contact you again here about this.
In any case, you shouldn’t need to keep a significant amount online. Only keep a small fraction of the total sum of user balances.
with regards