Good news,
someone Bitmain Technologies Ltd. put up some nice graphs to monitor the fullness of blocks (not blockchain.info, but I hope you can give others a chance as well).
https://www.btc.com/en/stats/block-sizeOf the past three months it shows
- the median daily blocksize
- the average daily blocksize
- the number of daily transactions
- the sum of daily blocksize
It also shows monthly graphs for all time as well. I think that once the median monthly blocksize hits 1 MB, it can be said that blocks are definitely full. For the first three months of this year it was around 933 kB, or 93%.
I know that the party line stipulates that many if not most of the transactions are spam and shouldn't be counted. But that's a different topic.

Thank you for providing more information about possible sources to support some of the arguments that you had been making (regarding blocksizes being full).
Some of the data on that site make little sense to me, however. I don't really understand how they are calculating average blocksize as compared with median blocksize, and why there would be a difference between those two concepts (except through their definition of such).
I believe that some of our valid criticism of blockchain.info has been that blockchain.info does not seem to be allowing for more granular analysis of blocksize, transaction fees and confirmation times, and so far, I cannot recognize that the various graphs of your provided site having more granular analysis.
Actually, if there were a way to break down into 4, 6 or 12 hour intervals would cause some additional ability to analyze whether there are periods in which transactions are taking longer to go through... Possibly, at some point, these kind of time issues will no longer be issues, because at this point, I personally can understand that sometimes it may take an hour to confirm paid transactions and it could take half a day to confirm low or no fee transactions...