1. If a company is doing voluntary layoffs they're probably not doing well. Usually the people who are more likely to find a new job, or otherwise more motivated, are more likely to take the package, so company loses best people. So just on general principle I would take the package.
2. Never consider just two options; minimum of three is much better. For example, you could get another job in US and pursue your ideas part time.
3. For your ideas, do some research. "Having an idea" in no way translates into success. Do you have evidence there's a market? Have you listened to potential customers? "Here's my idea, is it good" is not listening, everyone will say "yeah great idea" even if they don't care, just to be polite. Idea that comes from "I am an expert in this market and know their problems" is very different from idea that is "here's a random thing in an industry I know nothing about".
