The vote changes are really nice, It's just simpler to understand now, The other change that might impact some users (for the better honestly) is how keys work.
For the most part it will simply stop users using higher ranked keys (say owner key) for signing transactions that only need active, No more fallback, transactions that require active can ONLY be signed with active, same for posting, owner etc.
Will result in better security in the long run.
I saw that mentioned on the Hivefest discussion. Also something about multi-sigs. We need good security, but Hive seems fairly good generally. Keychain helped. Not sure how quantum safe it is.