Hitec and orion both have budget friendly DUO chargers. I have both and the software and user experience on the orion is much easier to use imo. My son uses the orion due to the ease of use. It is a touch screen.
as for quicker the higher capicity the more time. Always charge at the 1c rate( exactly what you are doing now). the hitec does have a fast charge feature but the charge stops at about 85% capacity so I just use the reg. charge.
good luck