Don't get despondent mate, I'll help you work through it.
All we need to do is break the cycle.
Make sure your death care is dispersed throughout the city to ensure they don't all get caught in a traffic jam once you turn up the Healthcare budget to combat a death wave.
Your death care should be able to cope with a constant budget of about 75% on tick over, so make sure you place deathcare and healthcare building appropriately for this budget so that you can ramp it up to 150% once a death wave strikes.
Also try to stagger the zoning of your residential zones over time as well as size.
Edit: I have to goto work now. Will be on later tonight.
I did pretty much ALL that. I used to have a cemetery on top of crematoriums, did ZILCH to help with the deathwave problem. It only made it worse because once it gets full, it can't be used and I am all of sudden 10 hearses short. I got rid of it now because I don't need it really. With this new crematorium mod, my total capacity of crematoriums are 2000 like I stated before and that's MORE than enough to handle all the dead corpses of the entire city. Crematoriums are NOT the problem.
And as to placing the crematoriums all over the city right in all of the zones, that's NOT something I am going to do. I am NOT placing crematoriums right in the middle of downtown prime real estate right beside high class condos and offices so people are constantly ingesting fumes from the burning of dead bodies. I come from a culture where we believe that the dead is to be separate from the living so I have all of the crematoriums placed at the far end of the other side of the city and all the hearses have to travel across the city to my "living" zones to pick up the dead instead of having them in every single block of the residential and business areas. That's just eerie and disgusting!! Even though there is no traffic congestion because my city's only got 40K+ population and the hearses travel on highways and 3 lanes+ roads with speed limit of 60 to collect the dead, maybe the distance is the problem but I am NOT compromising on this. I am NOT having the dead mingle with the living.
The game is supposed to be flexible enough to accommodate all styles of city building and not force players to play according to some stupid ideas of the game dev's especially the root cause of this problem is still that the death occurrence is not supposed to be set at a certain age and people just spontaneously die when they reach that age. If they had set the death rate to be in relation to variety of factors and randomized which is what it supposed to be, this problem would NOT happen no matter how far you place the crematoriums. I am NOT compromising my playing styles derived from my beliefs to accommodate some cop-out design flaws. If I don't "win" this game, so be it.
Thanks for your help. Great talking to you and nice city!