Nah, GOP establishment / elites just unite under someone in 2019 and do what the Dems did with Clinton, push them as the safest chance of winning and go forth. If recent history is a guide, the GOP will be desperate enough to win that they will pick a moderate republican and the primary voters will be basically told "if you want Hillary gone, then pick XYZ moderate candidate". Happened with Kerry in '04 and Romney in '12. I think the key is to pick off all the potential primary candidates in 2019 with promises if they back the establishment nominee.
Losing 3x in a row has a way of making a party sort of salty and uniting primary voters, oddly enough. If Ryan hadn't lit his career on fire w/r/t Trump, I still think a Ryan / Haley ticket would be pretty hard for Clinton to beat. I think Haley is a good bet for the VP pick (and depending on how the next four years go, even a dark-horse pick for president.