I guess the balance of things really depends on how close yoy are to the hospital, how much help you have and for how long, how the older ones are handling things, and if you have a pump at home assuming you are breastfeeding..
Take things day by day and assess who needs you most.. I your hospitalized one is currently stable you can spend more time with your homebound kids and go to the hospital more if dc's conition were to change..
As for when to go, if you are okay with going later in the evening and just calling for updates during the day it probably is the best for everyone.. If you are feeling out of the loop request a care confrence with the dr, sw, rn, and case manager.. This can be very insightful.. Visiting during the day is hard because doctors are in and out, tests and procedures are being done and the staff is simply busier. If you call and request updates they have to stop what they are doing and help you, but it works out just as well.. As for your kids at home it would probably help them alot to have mommy there much of the time.. Now of course all this goes out the window when babe is unstable, people are sick, or there is a lack of helpers for the other kids.
Also remember that you said this has no end in sight, so don't where your self or your helpers down.. Keep yourself healthy and well rested so you can be there for your kids and babe..
good luck!