Unless you want to fly private jets, there’s no way around security lines. Signing up for TSA PreCheck is the most obvious way to streamline the process, and the most worth your time and $85. If you aren't eligible for it, or have just procrastinated signing up, plan your flights for slower times, like between 10am and 2pm, and after 10pm. And if you don't fly much, familiarize yourself with TSA guidelines before you go, so you can breeze through as much as the mob will permit.
Rental car lines
For some reason, every single person in front of you at a car rental counter needs the concept of a collision damage waiver explained 14 times. Assuming you don't, the process can be amazingly fast.
Rewards programs are the big time-saver here. They allow you to enter your driver’s license and credit card info once. Then, every time you reserve a car, it's waiting for you to drive away. Hertz Gold Plus Rewards, for example, has a big board with members' name on it that directs you to your car, no line required. Avis has an app that allows you to not only rent your car, but also change it on site, unlock it, and return it without assistance. Alamo has automated kiosks for its members. These aren't always your cheapest options, but if time is money, the inverse is also true.