Is learning to draw a valuable skill for one who wants to learn 3D Character animation (and modelling/sculpting)??
Don't get me wrong. I love to draw people and portraits (There's always room for improvement though). But as I have a full time job I'm finding it hard to decide how to fit it into schedule.
I would say it definitely is worth learning, at least the basics with some advanced drawing skills.
Learning to draw faces and bodies will help you understand the human anatomy from an artistic side better and transfer into your 3D characters, since you are probably going to sculpt faces etc.
In my opinion I would even go as far as to say that they go hand in hand, since building a 3D character based off a concept art piece is a lot easier and smoother to handle than just starting to build or sculpt a rough idea that's only in your head.
Elen has a point, take her advice.
All you need to draw is a little notebook and a pencil you can carry with you all the time and doodle something when you are waiting for the train, bus, at lunch- or coffee break, at the dentist waiting room or when you are waiting for the girl when she is late again. If she finally shows up you tell her : "hang on chérie, I just have a bright idea." She’ll be in time next time :-)
In regards to fitting into the schedule I would just ask yourself how dedicated do you feel to learning these aspects in future or how quickly are you trying to learn? Do you see yourself only wanting to dabble in this for a short time or maybe see yourself still doing this down the road for the next 10 years? Even over the next two years you have 8760 hours to practice. You can still do a lot with say 30 minutes each day on either computer graphics learning or drawing. All the better if you can already draw somewhat well ;p
There is much to be said for even the small amount each day that builds up over time compared to say driving large portions of time once every 9 days or something. Either way I would say it depends upon if you can find reference material for what you want to make. if you can get it easily you really have no need to make your own reference material.