Hey TigerScrum
Kicking drill:
Box kicks have become an important part of scrum-half play, especially recently. I'd make learning this way to kick the ball a priority. Stepping back and putting the ball for an up-and-under (garryowen) is fairly simple, accuracy is an issue most of the time bacause of the swinging action the leg makes when kicking this way. You have a small range between putting the ball directly out to placing it smack bang in the center of the field.
One way to get your accuracy up to scratch it to try this kicking style while stand on the sideline, using the line as a gauge/measurement of your accuracy. Try do the full motion when practicing. Doing the back step before you kick the ball is vital because in the match situation you'll have players in front of you, obstructing your kicking height and angle.
Another nifty kicking technique to have done right is the grubber/cross kick. Fourie Du Preez, the best player in the world, uses this superbly. When a player does a crash ball, particularly in the midfield, the defense will be up & flat straight after the ruck is formed. Getting to the base of the ruck quickly and nudging the ball to the sideline, behind the now flat defense, can play havoc with the opposition winger and can create opportunities for your winger. That's just one example of how a grubber kick can expand your influence in play, I'm sure you can come up with more ideas on how to use this.
Passing drill:
The snap pass is an important technique to have in your position. One way of getting better at this is lining a few balls (say 5 balls) on the ground, about 5 meters apart, lying as it would be after a ruck (pointy sides facing the sideline). Start your run-up about 5 meters behind the first ball, coming at a 45 degree angle. It's important that you come in at an angle as the time you'll use the snap pass is when the ball is being moved, so they'll most probably be coming from that kind of angle rather than dead-on.
As you're coming in, say from the left & passing right, pick the ball up and pass in one movement and carry on your run. It's important that you do this while running (fast jog), to help with the momentum since the whole point of a snap pass it to not 'cock' the pass, so to say. It's a quick flick of the wrist that gets the ball going.
Now you'll be line up for the 2nd ball but in the opposite direction, do everything the same but just opposite. And I mean opposite! Opposite passing action, opposite leg used in the passing stance, everything!
As a scrum-half you must be able to pass both ways. PERIOD. That's what separates the Mike Phillip's to the Fourie Du Preez's in this game.
Another tip to improve your general passing and handling is playing touch rugby. Touch is very popular among the youth of New Zealand and that's why imo they have the best players with ball in hand. It helps you get the fundamentals of handling and passing while having fun. Try it.