I'm not aware of more recent discussions but I found the first three pages of
this Feb 2013 thread good food for thought.
I've read the initial post of that thread several times and I think that its headline is a bit misleading. Essentially what Peter Todd is saying is that an large blocksize limit in general encourages the miners to drive out low-bandwidth competition. He is actually opposing Gavin's plan as well:
It was simply that many heavy-hitters were expressing opposing views that I found the thread informative.
According to Peter Todd it is essential that miners do not control the blocksize limit. He argues based on the assumption of an rolling average mechanism that takes its data from the previous observed block sizes. But that's not an argument against a dynamic block size limit (increase/decrease) in general. The point is, that the dynamic block size limit should not be able to be (substantially) influenced by miners, but instead by the transacting parties. So if it would be possible to determine the dynamic block size limit based on the number of transactions multiplied by a fixed "reasonably large" size constant plus safety margin you would get rid of the problem.
Certainly, a dynamic means of adjusting the block size which could not be gamed by miners would be great. Linked by Peter was an idea from Gavin of determining an appropriate block size by the times taken by nodes to verify blocks.
Unfortunately, I'm not aware of any proposal which really does this. I don't know the precise details of your proposal and currently don't see how you intend to guard against large miners simply creating millions of transactions to trick the dynamic algorithm into thinking that very large blocks are needed.
I'd better say: "Only raise block size limit if required by the minimum amount necessary."
What constitutes "necessary"? What if there are so many "necessary" transactions that it's impossible for Bitcoin to continue as a decentralised system? I'd like to see as much block space as possible but will happily work to keep the blocksize smaller than many deem "necessary" to avoid centralisation.