I was stationed in a much smaller urban community than LA, but it was still urban. We didnt have any major high-rises as that creates a another dimension of hazards, but still, overpasses, aerial wires and power/telephone poles make good substitutes.
I think you have a pretty good plan
just solidify, modify, and make sure you have an alternate route or two (both to your parents and to your own home) and do a couple of what we like to call ROC drills (Rehearsal Of Concept). This could be as simple as drafting on a piece of paper, rehearsing on a map or even running a couple of dry-runs. This helps to war-game possible problems/potential issues, etc. and allow you to continually modify (really important during changes of season/weather).
I really like the bicycle idea (something I need to add to my own current get-home situation). Even if you bought a second-hand mountain bike, you could leave it at your parents place if your car is out of the equation. Additionally, I would ask to leave a tote or two of cached gear at your parents; just a change of hiking-type clothes, extra batteries, water, snacks/food, etc. for your longer trip to your home.
Now that you have some of the bigger concepts in motion, start considering the hazards and ways to mitigate them. Once a catastrophe or crisis hits...
First thing to check on are injuries; have a decent FAK.
Second is going to be immediate threats/hazards such as fire or structural problems in the building. Evacuation may be the next biggest challenge.
Communication will be critical; ensure you have the text option on your phone and dont forego signaling methods (flashlight, bright bandana, signal mirror, etc.)
Once you get away from the worst of the danger zone, you need to get yourself oriented for the next stage of planning if needed.
Food and water are always good to have on hand as your body will be under a tremendous amount of stress. Hydration will be essential to keeping your body and mind functioning at optimum levels.
What are your most likely regional threats?
First, consider your most-likely threats for your area; fire, flooding, earthquake, tsunami
are there any major chemical plants or railways in in the area? There have been accidents of dangerous chemical spills creating another potential hazard. Yeah, I know there is the threat of aliens, Charlie Sheen and even the weekly Sci-Fi asteroid catastrophe, but you really need to apply a little most-likely scenario assessment. Considering your area, earthquakes and possibly wild fires would be the most likely.
You have some potential obstacles. It could be the need to evacuate out the window 3-4 stories up. Navigate the office/stairwells in the dark or with smoke. Consider having to maneuver through and around broken glass, concrete, exposed rebar and falling debris. We often refer to these protective essentials as PPE (Personal Protective Equipment). We also focus on head, hands, ears and eyes. Ears may not be a big issue, but having a good set of leather gloves, ballistic eyewear and if you had that bicycle, you could have a simple bike helmet to prevent serious injury from flying or falling debris.
Another serious consideration would be a simple dust/smoke mask
that would be essential for navigating in an urban area after a major catastrophe; one item I would strongly consider.
Tools will vary depending on your situation. I really like fencing pliers as they can be used as a wire cutter, hammer, pry bar and even a weapon if needed. A mini crow bar would be another good addition. I would also recommend a simple set of adjustable pliers
many uses and even give you the ability to access potable water in a water heater.
If you have to evacuate out a window a few stories up, there are some excellent personal rappel devices (simple 8mm rope, mini belay device and a carbineer or two) that are easy to use with a little instruction and practice.
Dont forget water! I would keep a case (or two) at work, a case in my vehicle, a case or two at my parents in the cache and carry a bottle or two in my bag. With any major catastrophe in an urban area, most utilities get interrupted
meaning no electricity, no functional plumbing and potable water will become a premium. Along with water, consider batteries. Without electricity and only emergency lighting in some areas, navigation inside buildings will be impossible without a quality LED flashlight; have plenty of batteries on hand and cached. I always EDC an LED light (presently a Novatac 120 mil model), but having a good headlamp in the bag is a great backup and illumination tool when you need both hands free.
I know you have planned routes, but make sure you have good city maps. You should have all the choke or danger points identified
bridges, major on/off ramps and freeways, (dont forget to identify the more seedy areas of town for avoidance), tunnels, drainage areas, etc. Also look for less probable routes to avoid mass traffic
power lines, railroad tracks, drainage ditches, etc. Maps are going to be critical along with a simple, inexpensive AM/FM/Emergency radio will help to get information updates after the crisis hits and possibly avoid congested areas or other hazardous areas. A police/emergency scanner wouldnt hurt either! Also, make sure you have text on your cell phone as it will most likely be much more successful than a phone call.
With all that for consideration from my own little foxhole when in a smaller, but similar predicament for planning, here is was what my urban get-home kit consisted of:
I cant remember where the list was for my loadout, so hopefully the pictures will do. If you have any specific questions, I should be able to address them as I put a lot of thought into this kit for my own needs and most-likely scenario planning.
ROCK6