Many of the top tier GOP females (Nikki Haley as one example) are young enough they can punt until 2024.
Kelly Ayotte is 47, Haley is 43, Joni Ernst is 45, Mia Love is 40, Kristi Noem is 44, Martha Roby is 39, Elise Stefanik is 31. Hell, even Palin is only 51. Not saying these are good candidates, but they're reasonably popular in GOP circles and have plenty of time to bulk up the political resume more.
A lot of their "Presidential age" women aren't really good national Presidential level candidates, Mary Fallin, Susana Martinez, Jan Brewer, Lisa Murkowski, Shelley Moore Capito, Deb Fischer, etc.
Of course Debbie Wasserman Schultz is only 49. So her 2024 campaign will be a major threat.
One I wasn't fond of was Edwards seemingly randomly bringing up Dick Cheney's lesbian daughter in their debate. After reviewing it not too long ago it wasn't as bad as I remember, but just the design of the tactic is somewhat crass.
Of course, Edwards turned out to be a real scumbag. And creeped out John Kerry of all people enough that he told campaign staff to keep him away.
That said, I wouldn't mind if we reverted to our old not-lying-to-ourselves ways of campaigning, which Trump is closer to, so I probably shouldn't complain about what's really minor things historically. And really, pretty tame.