Compared to most newer tractors your 2n 3point will always seem slower when raising.
If it’s cold when you start the 3point will be extra slow for about the first 20 minutes until the oil actually gets warmed up so it flows better, the colder it is the longer it takes for the oil to warm up, it’s ok to use it with cold oil, using it will actually help the oil to warm up a little faster.
I plowed my pretty large yard and driveway with a 8n for over 30 years.
Mine was starting to have shifting difficulties a few years ago so I checked the oil and it was about it was about 2 quarts low so added oil and it has been shifting perfectly since, I prefer to use the dipstick but I’m sure the remove the cover bolt method that John0829 mentioned probably works fine as well.