Nothing is thin in the 350 route structure, especially the 35K. Yes it has better range than the 359, which does have issues on 16 hour flights. I'd expect initially it will be more capacity on routes that need the lift like JNB, MEL, SYD and ATL-ICN, ATL-PVG. That will free up a few 359s for SLC-ICN or some 339 city pairs that are PO. As the fleet grows, there will be opportunities for more 16 hour destinations. Yes it could be used to sell more seats in slot controlled airports like LHR.