The balancer is designed to make sure each cell is balanced in regards to voltage. You don't have to do it everytime you charge, maybe every 5-10 charges I would think to be on the safe side. Also as for charge rate I recommend going with 3.8v for your 3800. Sure you could charge a 5.0v but that will shorten the life span of the battery.

Also does your esc have a lipo cutoff? If so I would set it to 6volts. If you don't you can get an external lipo cutoff. This ensures that your lipo doesn't drop to low voltage which in turn can cause bad things

Hope that helped a bit.