To me my tractor is a tool. Tools get used and get dirty so I don't go overboard with the cleanliness thing.
HOWEVER
I do find that an annual or semi wash and clean (to a degree) is my best excuse to go over all nuts bolts fasteners etc.*
I am also guilty of using touch up paint on nicks and scratches. As a result my 1980 something tractor is very presentable for a tractor that lives outdoors.
But then I am fortunate that most of the paints on my Mitsubishi can be matched with Tremclad 'out of the can' paints.
In the fall I do wax my hood simply because the snow slides off more easily.
I also like to squirt some oil on all 3-point joints and leveling screws so that they don't rust/seize up.
All in all my tractor looks used but not abused but always presentable and not 'concours' quality.
* amazing how many fasteners get loosened over time.