Some time saving activities we use all the time:
Single Ride Test Track at ECPOT while still designing your own car
You can go into the exit of the attraction building and go into the design salon area. There are a few terminals to design a car just as you would in the stand by queue without the long wait time in the stand by line. Also helps out with FP+. You don't have to use one for Test Track and can grab three more in EPCOT that day.
Walk between EPCOT & Studios
If you exit EPCOT via the International Gateway, there is a paved walkway all the way to the Studios that only takes around 20 minutes to get between the two parks. Beats going out the front of EPCOT, waiting on a bus then the ride to the Studios. Works on the way to EPCOT as well. You just enter through the International Gateway.
Left side of the queues
We always find (for whatever reason) the left side of most queues seem to go faster than the right. Have no idea why, though at Tower at the Studios, we always go to the left and seem to get on much faster than people in the right queue. Same at the Mansion at Magic.
Ride marque attractions during parades or fireworks
Riding big name attractions at each park during shows, parades or fireworks offer a shorter wait time than during "regular" times without the shows/parades occurring. Depending on your visit, you can always watch those shows at another time. A lot of people watch these shows and will not be in the queues.
Rope Drop
If you can stomach getting up that early. It's a good way to knock out at least two major attractions at a park without having to use a FP+ on them. ie. Toy Story, Seven Dwarfs, Soarin', etc. We've rope dropped Magic and were able to ride Space & Seven Dwarfs within 15 minutes without FP's and used them for the Mansion, Thunder & Splash going at Rope Drop.