Should I break each user_id up by each digit of the id?
No. It just creates extra levels for the filesystem to lookup, which slows things down, for no benefit.
Adding the date into the path however is a brilliant idea.
With the rise and rise of 'Social' network sites: 'Computers are making people easier to use everyday'
Examine what is said, not who speaks -- Silence betokens consent -- Love the truth but pardon error.
"Science is about questioning the status quo. Questioning authority".
In the absence of evidence, opinion is indistinguishable from prejudice.