The charger you now have will only do 1 or 2amps?

On the bigger charger you do need to connect the power plugs and the balance plug and choose the balanced charge from the menu.
You can from time to tim do a non balanced charge by only the power plug if you need a quick charge with the battery in the car.

If you get a battery with integrated 4 or 5mm bushings you do need a special charging cable that is not provided with the charger.

And up to 2C charging is pretty safe with todays batteries bur having a LiPo bag would be wise to charge and store your batteries in..