Well I'm coming at this from the perspective of a new empty-nester. I look back now and wonder how I had the time and energy to do all I did! Lessons, homework, drama (2 girls and 1 boy) and you know what? You just find a way. You just do it. Somehow, God give you the strength, the energy, and the willpower to get it all done. Of course, you do have to use common sense. There is such a thing as over-committing both you and your children. But if you seek to balance your time and don't let things get to crazy, it will be the best time of your life! I can't imagine life without my three, and if I had to do it over again, I would have had at least one more child.
It is hard when they're little because they are so helpless and reliant on you, but by the time my kids were three and four they were playing with their toys and entertaining each other, and of course I loved to play with them. I found it got easier with each passing year (until they reached their teens...that's always a challenge). I think the best lesson I learned was that they are each individuals. What works for one child might not work for the other. Just be consistent, let you know you love them each unconditionally, and realize that they'll be grown in the blink of an eye, so enjoy them while you can!