I've never heard of a "ramp check" in the UK - I believe they happen in the US, although I've never seen one first hand. But, from what I understand, it's mainly your license details and the aircraft's maintenance logs that they're interested in, not things like w+b.
To run through your list quickly:
NOTAMs: essential for any flight, but you don't need to carry them with you. In fact, back in the "good old days" of last year, my airfield used to stick a pin on a chart to indicate the areas where all the active NOTAMs are, and if there were no pins near my track, I didn't bother checking them.
W+B: learn you aircraft. My aircraft, for example, is normally re-fuelled to 3/4 tanks. I know that I can safely fill the tanks to full, or take a passenger, or take baggage. But as soon as I try to do two of these, I will do a weight check. I also know that if I take baggage and put it in the passenger seat, I'll be in balance, but if I want to put anything behind the passenger seats I have to check for a rear CofG. That's my aircraft. Know your aircraft, know what you can do safely, and do a W+B check for anything which takes you outside of the "safe" limits.
Perf check: again, know your aircraft. My aircraft doesn't even have any performance figures, so it's certainly not required! Know the take-off and landing distances at "normal" weights and at max weights on a "normal" day, and learn how they're affected by a "hot" day. ("Normal" and "hot" might vary dependnig on where you're located, of course!) Add a couple of hundred metres to those figures, and if your field is at least as long as the number you get out, then don't bother. If it's within a couple of hundred metres, then it might be worth getting the graphs out.
Flight nav plan is definitely not required, otherwise every jolly to the local area would be illegal! As would every trial lesson (and most other training which takes place outside the circuit other than navigation excercises). As would police helicoptor operations. And so on!
Basically, I think the message is don't worry - go out there and enjoy yourself!
FFF
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