Have you got a bus route or subway in there?
Yeah, the first metro route i put down happens to be where i put my first office block, previously it was farming (its now half & half), and there's also a bus route at one end too.
The same can be said of the 1 office block i put right in the middle of my highest valued district. It eventually appeared, ranked up to 2.6-2.7, then dropped to 2. I've left it for a while as i went to do other things, and the building has swapped from a newspaper to a law firm, which is odd cos i dont see it struggling to survive (all jobs taken with appropriately skilled workers).
This is the problem I'm having at the minute. Have 4 Incinerators and 6 Landfills and want to get rid of the landfills, but they have to be empty before I can delete them, as soon I start emptying them garbage starts piling up and the Incinerators dont seem to do anything. Seems like i'll be stuck with landfills for a while yet!
Ive gone full incinerator now, ive got 11 of them for a 50k population, and 3 more powered off (i went a little overkill!).
Its not foolproof, but open up the rubbish tab or rubbish infograph and it'll tell you how much rubbish is being produced per week, and what you can process. The reason its not foolproof is because thats only what they can destroy, you've still got to run it at optimum levels with vehicles collecting rubbish. I've got 329k produced, 528k capacity. I'd imagine you'd want to allow for 75% performance, so have 100k cap for 75k produced. It depends how far they have to cover how efficient they are i suppose.
If you want to use dumps and incinerators, try and make sure the 2 are together. This way when you want to empty a dump the vehicles dont have to travel far, so they can empty out pretty quickly, free up some space and let them get back to work again.
The same thing applies to dead bodies, except you get less vehicles with the crem than the cem (7 vs 10), while dumps & incin have 15 & 27.
Try and empty 1 dump/cem and if you start to see a build-up in the city then let them resume service.