Yup, I have many a track day under my belt and the dry nitrogen (keyword dry, not nitrogen) is needed for predictable changes in tire pressure as they warm up. Nitrogen itself follows the ideal gas law and expands with temperature the same as other gasses like oxygen, CO2, and "air." The moisture in "air" is what makes pressures unpredictable. Precise, predictable tire pressures are necessary when racing on the track. On the street and offroad, nah.
But, since you already have the tanks then you might as well make use of them if you've got the room. Faster than using a 12v compressor but not as many fills per tank as CO2, which I'm sure you know.
Sounds like you're having fun fine-tuning your new LR, I've always enjoyed learning and tweaking a new vehicle for what I want out of it. The truck in my sig is the first vehicle that I haven't grown bored of, which my wife is ecstatic about because I used to get bored and buy something new every 1-3 years (I think my vehicle tally is something like 24 at this point). Took forever to find something that wasn't full of compromises.
Take care! Looking forward to reading about your progress.