Wow looks like you have a lot to consider here. You mention many things: intellectual property (copyright and trademark), incorporation, contracts (web agreements) and immigration concerns. As such, you really should speak with a lawyer.
The reason I immediately suggest hiring a lawyer is because there are differences between the two entities you mentioned which may have varying effects on your company that you may not desire. Foreseeing these potential issues is not the easiest task, and mistakes can be made even with some detailed research. A lawyer who has worked with startups in the past and has business law experience will be able to give you sound guidance that could end up saving you a lot of time and money. This is especially true for visa holders such as yourself.
You should take a look at our site. We are currently helping thousands of startups find attorneys that can best help them with situations such as this. I have founded two separate startups, and I completely understand how difficult and stressful the beginning stages are. But hiring a lawyer can not only help your company grow and succeed, it also gives you so assurance moving forward that nothing was overlooked. We offer free initial consultations and quick and easy price quotes.
I hope this answer helps! Please don’t hesitate to reach out if there is anything I can help you with. I am always eager to give a lending hand to a fellow startup company. Best of luck!