I think if the type of infringement that NATS/CAA/ etc are really concerned about was edge nicking at corners and underlying airports, then there would be merit in smaller size/ better alignment to ground features. But most of the high risk ones are people blundering straight through controlled airspace. Lets get that one right and then look if we have a problem worth solving on the edges. (Yes I do know that traffic could have been at the edge, and yes it still does close 5 mile radius, ground to altitude + 5000 ft, but we have to start somewhere)