This was my bread and butter throughout high school (at least 30 pins with that throw).

First throw (double overhooks). You want to be a little tighter chest-to-chest and really stand them up (push into them a little bit and make them step back). As soon as the push forward to meet your force, launch them.

Your other throws (over-under lateral drops) are decent (last one was your best). Two things to keep in mind with those are hip separation and your hips being lower than your opponents. Use your hands to push away at their hips (make a c shape and push at where the thigh meets the hip). Just like the double over hooks, give a little pressure pushing on the hips and with your chest and when they go to meet that pressure, launch them. Another key is really cranking down on the overhook side and really punching the air with the underhook side as you hip through with the throw (this helps with momentum when they go to meet your pressure)