Is there anywhere to find more specific information about difficulty-- eg. What is the current target value for candidate block hashes?
If you have Bitcoin Core, you can query the current target with
getblocktemplate "{\"rules\": [\"segwit\"]}" command.
For the difficulty, you can query the exact difficulty with either one of these commands:
getmininginfo or
getdifficultyThis webpage also allow you to execute some commands including those two:
chainquery.com/bitcoin-cli