Well, I can think of a few off the top of my head.
First off: motion controls. Learn 'em, learn to love 'em. I find that I simply cannot do anything useful with a charger unless I have them on. This is mostly due to the level of precision needed for the class in general. Being able to pinpoint a target without having to keep fiddling around with the R-Stick to get there is a huge boon for me.
Related to this is your GamePad's sensitivity. A higher sensitivity grants you more control over where you aim, but unless you have super-steady hands (which I don't), it will also get in the way of aiming. I keep mine at -2 for that reason, but you might be able to handle a higher sensitivity... or, perhaps you're even more jittery than I am, in which case toning it down a notch would be a good idea.
One thing I've seen most of the better players do is hide their shot until they're ready to fire. Being that a charger's laser pointer instantly gives them away, the idea is to maintain your secrecy until the very last moment. I personally don't do it myself, but I'll admit it'd probably come in handy.
Speaking of secrecy, you should also take gear abilities into consideration. Ink Recovery Up is one you'll definitely need, as keeping a full ink tank comes in handy for weapons that eat up a considerable amount of ink per shot. Damage Up is another common sight, as it allows you to splat a foe without fully charging your gun. If you're more about keeping stealthy, Cold Blooded drastically reduces the time spent being tracked (from like 11 seconds to 3 seconds, I think).
This thread is a good starting point to check what abilities work best with a given weapon.
Now I'm as much of a newb with chargers as the next guy, but I hope this helps somewhat.