Balance can be achieved solely through your faders and fader automation, with well-recorded instrumentation that had the mix in mind at the time. Otherwise, you'll have to use eq and/or compression to fix things.
I would just like to chip in again here.
In my experience, (making major label records for 30 years) the best way to arrive at a great end result, is to get it right at the beginning of the process. I'm a big believer in "fix it in the mic" if you don't start with a well recorded source, it will be much more difficult to get the end result you're looking for.
A good quality microphone and preamp (preferably a channel strip) will teach you more about sound than any plugin can achieve. You need to have the finished product in your head before you put up the first mic. That way, when you are recording an instrument, you can reject anything that doesn't match the sound in your head. Learning mic choice and placement is where you start to train your ears and learn about sound.
I've only been lucky once or twice in my time to pull up the faders to mix a track and find that I'd got the tracking so "right" that it was pretty much just a matter of balancing the levels to end up with the mix I'd envisioned at the start of the process.
Indeed!