Doing plyometrics exercises to increase vertical leap is the only way to achieve the results that you really want.
In order to jump higher than you have ever jumped you have to train like you have never trained.
Jump training is all about knowing what to do, when to do it, and how often you should do it.
I will help you out so that you can start getting some results from all the working out you have been doing.
First off you never want to do plyometrics right after you work your legs out.
The whole point of doing jump training is to do it when the legs are fresh.
If you lift weights right before you start you jumping exercises you will not get results.
I'm not saying that you shouldn't train with weights, only that you should do so on opposite days as your jump training.
Now when you are doing leg strengthening exercises you need to focus on having some explosiveness in the movements and not just on doing the weight to do it.
So you might use slightly lighter weight so that you can lift it a little faster.
You are trying to find the perfect balance of weight heavy enough to increase your strength but you don't want to sacrifice speed.
The amount of repetitions you will be doing is going to be under ten always.
Make sure that you use a weight that will be hard to do 8 times.
This way you will train for explosiveness and not for endurance.