Essentially, our entire divorce/family law industry stands behind you getting your children and the father paying you support.
As to legal details, it seems from your facts that you are the primary caretaker of your children. A lawyer will be able to make out the case that it is in your kids' best interests to remain with you.
The Child Support Standards Act will guaranty to you a 25% cut of his pre tax pay minus FICA, Medicaid tax and local tax. This 25% is then paid out of post-tax earnings and is only the basic support amount; there are nine other add-ons that could jack up the support amount. If you have been married for a while, your state should give you a bigger chunk of your marital property as well.
He will stand little chance at getting the children. The Child Support Standards Act pays matching fund money to the state, so the state is not going to give him the kids for you to pay next to nothing in support. In general, the dominant earner pays support and the state gets the greater matching funds. So, it does not matter if you are a good mom or a great mom.
This means that despite local law providing for an equal shot at custody between men and women, each case is set up to provide the greatest challenge to the father in obtaining custody. Typically, the more he fights, the greater the number of obstacles placed in his path: psychologists, guardians ad litem, parenting coordinators and visitation super-centers.
You can lose your kids because of other federal policies.
For example, if you are the one taking illegal drugs, that will trigger a reversal of custody because the feds are at war against drugs. The local court will make it look as if they are the ones making the "legal" decision in the child's best interests, but instead, it is the federal policy that drives the train because there is likely more federal money involved for child protection. If your lawyer is able to show that the husband is the drug user, then he will be precluded from being the custodial parent and may even be limited to supervised visitation.
An allegation of child abuse will trigger a reversal of custody because the fed is all against child abuse.
Family Law was the "healthcare debate" of the 90's but there were no town hall meetings. Congress quietly reformed welfare with these new policies and a visit to the local divorce court now could be a rude awakening.
Never go to court alone. Have competent counsel with you and make no move without that counsel's advice and guidance. Perhaps that counsel can get an order making your husband pay his fees to level the financial playing field between your husband and you.