I didn't suggest the ORD incident was no big deal. Thankfully the 737 was light and flew well over the 747. It could have been a disaster if it was a departing heavy 747. The controller screwed up, end of story.
I think most pilots that are familiar with the airport they are flying into know which high speed they want to exit on to be efficient. Landings on 9 at Miami which is 13,000 feet and making the first available turn off pretty much guarantees that you will be following the plane landing behind you when you finally get up to the high speed he exited on. It isn't that hard to be both efficient and safe. Getting the landing clearance for the full length of 14R is probably standard procedure for Atlas to minimize their taxi time especially when the airport isn't that busy.