I ride my bike over various distances and it does not matter what distance you do- you do need to carry a few spares. Mainly to appease the flat fairy but I carry a pump on the bike and a small saddlebag- called a wedge- under the saddle. In that wedge will be 2 x tyre levers- a spare tube- a puncture repair kit and a Multitool. Then other than a Water bottle and carrier there is nothing extra on the bike. Admittedly for longer rides I put a larger bag on to carry an extra tube and some food but that is it.
I always dress for the "Expected" weather and I may wish to carry an extra coat of some kind- or take a layer off- but my final topcoat will be lightweight and pack into a small package that can be carried round the waist in it's own bag or stuff into a jersey pocket. Last weekend I did a 100 mile ride and I was surprised at the number of riders with panniers or large backpacks to carry their extra stuff in. No idea what was in them but I feel that carrying all that extra weight is a waste of energy. I have enough problems propelling myself up the hills let alone a lot of surplus weight that I do not need.
Below is a picture of my bike as on the ride at the weekend and the only extras on the bike are the lights. It has the large saddle bag on it and this will do me for 100 mile rides. I will admit that I also had on a 2 litre Camelback and in the small pocket I had my phone and wallet. My jersey pockets had some food and the camera and that was it. I finished up wearing the Pertex top right from the start and that was why there were not many pics on the ride as I could not reach the camera with ease but that would have been in the pocket if not used.
I do realise that some of us will ride in remote places and may have to carry a few extras for safety reasons. I also ride a Tandem offroad and there will be extra for that like a spare folding tyre- a spare chain and chain tool and possibly instead of the Multitool I will carry proper tools but that is because the Tandem breaks things easily and on our long rides we always had a back up vehicle carrying spare wheels and extra chain and tools but that is because you can't pick up Tandem spares at the normal Bike shops or repair stations on rides.
So what do you carry on rides? or am I just taking a chance by wanting to be a lightweight on my rides?