If you get married and apply for a spouse residence/work permit before your 90 day visa expires, you'll be fine. Whether you think the process is easy or difficult depends on your level of tolerance and previous experience in other countries. It's best you get used to bureaucracy as a non-EU citizen in Greece. Also, I'd like to note that having a residence/work permit does not automatically make you more competitive for jobs, though it does solve legal issues.
You can only marry in a civil ceremony unless you convert to Orthodoxy.
Here's an article that pertains to you and your future wife:
http://americaninat...greece-the-bureaucracy/
