The Ranger Javelin doesn't have the same number of hidden mechanics as the other Javelins, but that is mostly due to the overall fluidity and short animations on all of the Ranger's abilities. Very rare are you ever locked into an animation for more than a fraction of a second, unlike Storm and Colossus.
Even still, there are a few tips and tricks that will help you cut through your enemies a little faster and easier.
Using the burst of speed granted when you initially hit your melee button, you can fling yourself forward with a quick jump. This is best used when carrying an object that won't let you fly, or inside of a grounder field, but it can also be helpful to quickly move to an enemy a short distance away.
Just like the Interceptor, you can use the melee slingshot in the air as well in order to speed up your travel or just go further on your thrusters. A quick melee and immediate jump will catapult you forward significantly faster than flight speed while also giving your thrusters a break.
A bit more basic here, but something every Ranger should be aware of. Your ultimate has 12 missiles, which are spread evenly between all targets inside of the large reticle. You should try to learn how many missiles you need to kill larger targets like Valkyries or Enforcers and make sure you fine tune the targeting in order to kill the most dangerous enemies. The HUD will show the number of missiles locked on to each enemy by the dashes that appear around the inside of the red targeting icon around them. Sending 6 missiles at a single shocktrooper is a little excessive.
Not only are you far more likely to actually land your hit on target when jumping first, the aerial melee has a respectable AoE effect which can detonate or prime several enemies if they are grouped up. Ground melee tends to completely miss frustratingly often, but if you land on an enemy from a jump, you will pretty much always get the hit.