If you had a bigger tractor it might be more of a problem but those economy series tractors are excessively light to start with. The tires on my
L3800 are loaded and I can’t see any good reason you’d ever want to take it out. I’d slap on cast weights in addition to the fluid if I had them. The weight will make traction better not worse. The front tires cause more compaction and turf damage. What weight the fluid adds really doesn’t change that aspect. Any ride benefits with such a small tire to start with would be extremely limited. You’d accomplish a lot more to throw away the crappy seat. If you did happen to have a good reason you would just drain the tires and be done with it. You definitely aren’t going to load the tires for one job and unload them for another. If you had iron hub weights you aren’t going to be taking them on and off either.