I'm new to the site this week, the Virtual US Open sounded like fun. Unfortunately, it's not, due to the assumptions and limitations of your code and design, NOT because Bethpage Black is a tough course....
The most glaring flaw in your logic is starting everyone at the HACK tier. This limits what you can do with the starter clubs. Instead, you should start without a tier, and only assign a tier after 5 rounds, just like the USGA handicapping system. If I can't play, I'll earn HACK status, but don't put me there by default and limit what I can do within your game structure....
As much as you'd like to try to imitate real life...no, I won't be 'buying' a golf game....and I won't be wasting any more time on your game any longer.