My advice for jumping, is to get a good launch, and as you jump raise your arms creating momentum.
Make sure you balance your tori so its up right and not flipping.(Unless you're flipping)
Also for fluidity, when you are doing a trick or some kind of attack (say a punch) while you are about to punch,
and you have all the momentum, Relax all and see what happens.
Only edit the joints that will stop the momentum from spinning you too much and keep you balanced.

I made a replay that will hopefully help you. Look at how I use my arms to create momentum,
and most of the time I am mostly relaxed. (added the mod too if you don't have it)