First things first. In the new warzone, when you collect the orbs you need to run them back to your own pylon to get points. The debuff you're waiting for is how long you can take running it back to your pylon.
As far as key binding go, a gaming pad like the G13 is a huge benefit. it says 79.99 but I picked mine up at bestbuy for 39.99. With this I don't need a gaming mouse, just a regular mouse with 2 thumb buttons. Thumb stick for movement and use one of your mouse buttons as a shift key. Easy learning curve, naturally rest your left hand on it and have no end of keybindings that make sense.
A tip for healing with a scoundrel. CROUCH. You can crouch just like the snipers can, making you immune to leap attacks and grapple as well as giving you a defensive bonus. You can still heal, attack, and cap nodes while crouched so practice using it all the time. The roll function can also be handy for quickly getting out of tights places, or those death from above attacks you hate so much.