Here I'm not splitting it as much as I usually would, just for the sake of time. My primary goal is to eliminate all 'inner' areas, so I will divide the landuse along a road that helps me to reach the area (eg a school) so that I can exclude it while only using simple polygons. I will definitely make sure it's split by primary, secondary tertiary roads, and then also split off sections that are only connected to the main blob by a relatively thin area. In places I've done to an extreme (i.e. Bushey, Herts) residential landuse never crosses even a residential road, lines up with property boundaries perfectly and has carve-outs for all other landuse like allotments, grass and substations. I have run some overpass turbo queries over Wales recently to find the absolute largest residential landuses and split them up.