I've seen it all and I'm all with you. Let's break it down into parts.
Why?
Because although I'm aware SPL fucked up in the past, it's innegable THEY TRIED and BUILT SOMETHING.
Since currently there's 0 accountability for funding proposals, why not this one? We are throwing x3 this money yearly anyway only with valueplan. In that sense, and I said it a couple of times, I trust magnitudes more 
We have to be logical about where we draw the line on ''funding/non-funding'' and above all be realistic and consistent with what we collectively decide.
I mean, there's no need to ''announce'' such a thing IMO. You as a witness setup your parameters as you feel convenient.
In addition to that, there's a overall feeling that top witnesses ''cannot be changed''.
This is simply not true. main problem is there's not enough people caring about governance and voting because ''my vote is small''. And in that sense, I agree, it's better to keep a group of stablished witnesses in order to guarantee some degree of stability.
Also remember that witnesses can't make alone changes in proposals, many of them do not hold ''that much'' HP.
Collectively without counting blocktrades, top 20 witnesses hold maybe a bit more of 10M HP (let's say 15M). This is still less than 10% of total staked Hive.
For voting something we still need a supermajority (since a lot of witnesses also vote for the return proposal.
Then there's blocktrades who can 'almost' control who gets funded/unfunded. However I remember read a reply of him in the past saying that he usually tries to avoid voting 'too much'. I understand he votes a proposal when he really has a very good reaosn to do so.
And/or the pros exceed the cons, u get me what i mean.
have a good day.
RE: Regarding DHF and HBD APR.