Good bicycle maintenance is the key. I ride 4-5000 km per year, most often with friends, groups of 8 to 12. I cannot remember the last time I needed a tool for my bike, the last time I used my tools it was for someone else. If you need a pedal wrench on the road, shame on you, you haven't taken care of your bike. By far, the most common on the road problem is a flat tire, trailing far behind is a broken chain.
You should never have to adjust handlebars or saddles out on the road if you are taking proper care of your bikes