One of the first things you may do after yelling off belay when leading a pitch might be to identify where the rope's gonna go. You'll be limited sometimes by the terrain where you set the belay obviously. As you gain more experience you may already have this idea in mind once in a while.
Using cracks, ledges, over your legs, shoulders, over the rope you may be tied into the belay with are all good ideas and some of them are too detailed for me to sit and explain pros and cons.
On some stance belays where there's not a good ledge I might coil it over my feet.
The key to me seems to be that you need to coil it with the intention your partner is going to lead the next pitch many times. The more attention you pay to the rope management at the belay the quicker you'll be able to dispose of routes and the less epics you'll have. I think it's one of the best skills to work at.
Just think of it like folding clothes for your mother and you don't want her pissed if you do it wrong. It doesn't have to appear pretty but just be organized.
Think of everything as a cycle for each pitch and make sure you include the step where you want your rope to go before you start telling your partner to follow.
If all else fails and everything sucks and there's nowhere to put your rope just have an epic and think about what you could have done later on. My guess is that you'd be able to figure out some ideas that would have worked once on flat ground
I own a rope bag but only use it for aid climbing and sometimes not even then. I don't think they are a necessity for 95% of free climbing including hook gadgets etc. However if you really like to organize like that and find it works well for you then go for it.
Just remember there are no rules in climbing as long as you get back home safe and don't hurt anyone else.