Being efficient at spamming is only a matter of how many accounts you have to perform it
This is not the case. It is a function of SP, which rate limits posting once blocks start to fill up. Small free accounts and especially even smaller mined accounts will not be able to do much.
You may be right that the allowable degree of bloating is still too high. It was reduced once and maybe should be again.
IMHO the allowable degree of bloating is working by design, which showed real capacity of the chain/network. When the chain is getting busier, available bandwidth of each VESTS will be less. By the way, the block size limit has already brought some non-ideal user experience, for example, long articles have to be posted as several part (and the API doesn't return too long content (not due to block size limit though)).
Aren't there two parameters, one controlling the maximum block size and another controlling the sensitivity of throttling when blocks start to fill? If I recall correctly, last summer both were reduced. I may be that it is better to leave the blocksize larger (for the reason you state) but further reduce the sensitivity to filling. (By which I mean allow less filling before bandwidth limits apply, technically that would be increased "sensitivity".)
The block size limit can be dynamically adjusted by witnesses. The other one, although is dynamic as well, is hard coded in an algorithm.
If you look at the account used by steemitmarket to perform his "test" attack, they have not that much SP and still were able to produce 86K posts in 10 hours.
Yes that is my point. The coefficients may be suboptimal for the current case of a lightly used network that still allows low-SP accounts to abuse.
@smooth, yes, https://steemit.com/bag/@steemitmarket3/steem-network-threatened