Something I'm happy about is if I can create an object to implement some isolated part of the domain in a way that's obviously correct and consistent within itself. For example, currently I'm working on a bit of a backup analyzer to identify different problems, estimate sizes and such. One object in there is the PGBackrestState and it has a whole bunch of one-line methods like total_size_on_disk, full_backup_count, average_incemental_size. Most of these are just one list comprehension. That's nice, readable, correct and stable code - and it makes other code more readable.
But some functions in that code base are an implementation of pretty much a flow chart of grabbing information, figuring out the state of the system and eventually dropping into more specific analyzers. This can be a whole bunch of imperative code in a function. And I've tried, but chopping this into smaller functions makes the overall idea and control flow much harder to understand. Sometimes a rough screen length of logic can be easier to understand as well.