You have waded into a complicated area of law in which the rules of evidence are central. A forum like Avvo is not designed to give anything but general information, so what can be said here won't be of much help. The likelihood of success will be dramatically increased if what you take to your modification hearing is your attorney, your documentary evidence, and your witnesses.
Best wishes for a favorable result, and please remember to designate a best answer.
This answer is offered as a public service for general information only and may not be relied upon as legal advice.
It's impossible to give you a useful answer without reviewing ALL the facts of your situation, but generally, a court is much LESS interested in information as to what is good for "children" in general than in information as to what is good for YOUR children, and why the current arrangement for YOUR children should be changed. Doing this on your own, without an EXPERIENCED family law attorney, is VERY difficult.
You really should consider hiring an attorney to put your best foot forward. You will only be able to request a change of custody and visitation orders if you can show a change of circumstance, so you really need to put forward the best argument possible. An experienced family law attorney will be able to guide you on how to convince a judge how to reach your desired result.
Since legal advice must be tailored to the specific circumstances of each case, and laws are constantly changing, nothing provided herein should be used as a substitute for the advice of competent legal counsel.
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