JB,
If you're thinking of staying in the U.S. to instruct afterwards, be careful of immigration requirements. Generally, non-immigrants cannot work in the U.S. except under very limited circumstances. Becoming an immigrant is a very long, painstaking process unless you have close family that are U.S. citizens or there is a U.S. company that wants to hire you and can prove to the Dept. of Labor that there aren't any U.S. persons who could fill the position (read: takes a long time).
As for just doing the certificates and ratings, that's up to you entirely.
Ray