Hi Rob
I know what you mean, the tweaking almost becomes an obsession. It can become a very expensive habit, so ideally I like to try to get it right first time. My post about my seasonal Bob problem is all linked into the same issue - buying the right gear for you, be it to your size, you experience, your everyday needs, your location, your work etc etc.
One item I do object to carrying around is my mobile phone. I hate the things, and I never have it switched on. I'm afraid its consigned to the bottom of my daysack most of the time, but I sure everyone has there pet hates.
I also feel I'm underprepared in some way...the trouble is we don't really know till "it" happens.