Unlike child support, spousal support is often very difficult (if not impossible) to modify after the divorce is final, so getting it right the first time is a must!
You may run into a sticky poin twith the health insurance for the kids, since you are under no legal obligation to support them. Most insurance plans will allow you to keep the kids on until age 21, and up to age 25 if they are in school full time. However, you may be asked to "prove" that it is a legal obligation.
If it is written into your divorce decree that you are obligated to cover 100% of this expense for them, then it may be possible - However, be sure you don't sign up for a legal obligation that may become too much of a burden in teh future (eg what if you lose your job?) Also, before you take on this obligation, check with your insurance co. to make sure they would, in fact, be willing to cover the kids under these cirumstances. It would really s#ck if you were forced to buy an independant policy on the kids because you "promised" this.