A man after my own heart you are, Craig. I resisted buying anything from this site for ages, and then they introduced the tiers and I was made master. After that I had no choice but to upgrade as I could barely reach the fairway on some holes, and I remember not being able to reach a par 3 green with my driver! It broke my heart at the time.
If you play purely for recreation you may get away with just upgrading your driver and maybe your 3 wood, but if you want to compete, you will need to seriously break out the plastic, and succumb to the capitalist regime, as someone once put it.
I remember having many a late night with me mates after the pubs shut playing that sega golf game in the early 90's. God, we thought it was brilliant at the time. Amazing how quickly things change innit?
Best of luck.
Sean