There’s so much trust in the field - in some people, who so far didn’t abuse it.
It might be harder to seduce those, who don’t do what they do, just for the money (and instead because they believe in what they do) by the money they handle…
Sooner or later something might happen; maybe an exchange defaults or gets hacked. But in my opinion that is something the collateral shouldn’t be used for. If collateral would be liquidated for that kind of issue, the fee for providing the collateral would be much steeper, than if the collateral would only be used for a service provider going rogue.
I think collateral is required or appropriate, if
- someone deals with big amounts without ongoing controlling
- there’s no track record of situations, in which trust could have been earned
- if there’s a frame work to efficiently handle collateral
- it’s used to make the person, who provides the collateral personally responsible (but not for failures of exchanges etc.)
But still we need to remember that collateral creates costs:
- opportunity costs for the one who provides the collateral (depending on what the collateral will be liquidated for)
- management effort (=costs) for those who manage the collateral
In the end the question boils down to which expectation value is bigger:
- the costs created by the collateral (without needing it) or
- the costs created by not having a collateral (if you had needed it)
I would rather insist on you not providing collateral than asking for one!
Let’s see how NSR holders decide.
If they don’t want to vote for you without collateral (ignoring that you don’t charge a fee for your service!), I’m going to make a proposal with a collateral (to cover my personal failures, but not exchange default etc.) - and 20% fee of the volume per buyback.
If NSR holders want to have exchange default covered as well, I might increase the fee to 30%.
How does that sound? 
If they don’t what that, they can hope that @Nagalim continues his role for
…without collateral 
I give your proposal a good chance to pass!