What do you carry now that you think you could get by without. If you have a large bag full of stuff you obviously think that each item in there will help you under some circumstance or another. What circumstances are you going to consider soo remote that you don't need to carry that item anylonger? Do you have more redundancy than you need for some area or another? Are you able to store supplies conveniently along your routine daily route? Such as in your desk / car / locker?

Try to re-align along a modular setup either based on scenario or function. Basing on scenario you will be prepared specifically for each day but it takes more thought when getting dressed and you will still have a bunch or redundancy as many scenarios will have overlaping needs you might pack two scenario bags with the same fire starting stuff. Basing on function allows you to completely leave out functions like "fishing / snaring kit" and add modules like "escape / extrication"

Hmmm?

What size is small? Are you thinking something smaller than an altoids? Are you thinking that the altoids PSK is not urban enough?

Basics:

Water, fire, blade, cord, shelter, FAK(an entire discussion can be held around the contents of a FAK later)

Urban additions

Escape / Evacuation / Extrication gear, SAR tools, Comms gear, Self Defense training / tools

Detail the above by your scenario profile. For example if your bag is large enough to carry a generic PSK + urban addons then stuff your Altoids tin in the bag and then start working on the urban additions. If you don't spend much time in high-rise or overly large buildings then you probably will be able ot ignore the EEE gear. OTOH if you work in a large building you might want a face mask / gloves / big bandana as a minimum escape setup to get through dust / smoke. A small prybar may seem overkill until you have to lever your desk of your broken leg in order to hobble out of the burning building. A spring loaded center-punch is de-rigor for any road travel including public trans. For comms gear you probably have the cell phone covered, consider adding FRS / GMRS / CB or HAM radio. If you scenarios include self defense then look into the training first and acquire only those tools that you have the time / money / inclination to train for the use of. Please, for my safety, don't go out and get a handgun without also training at the range atleast once a week and a course like those given by the lethal-force institute would be real helpful. Deploying and using such a tool is extremely effective but only if you are ready to do that. Same goes for any self-defense tool. Not saying you shouldn't get trained and equipped just that you are probably increasing your danger if you become equipped and not trained. (BTW, IMHO, this applies to all tools, the danger / effectiveness / training correlation is linear. Think matches and scorched fingers, knives and shortened fingers or guns and (accidentally) dead wives)