To try and compare WN to WS in terms of aircraft utilization, the 2017 figures are the ones I could find with a quick check. Their overall baggage charge policy hasn’t changed much since then. WS was actually a bit better at 11.2 hrs per aircraft per day compared with 11.1 hrs for WN, av stage lengths were fairly close. WN may theoretically have a tight turn time, but in reality it may not be often used.