Tax rates I am working on the principal that I raise taxes as high as I possibly can until the Sims and the Industry start moving out, and then I lower it again. I remember asking a colleague how much he thought I should charge for doing a bit of work. He said think of a figure and double it and then, if the person concerned complains, lower it a bit - but not to the original idea. I increased my bill by five times and no-one complained. Why not with taxes?
I don't think there is a set principal. I think best is adjust then accordingly. In SimCity 3000, I had to adjust my rates constantly to ensure I got city growth. However, when my city became large enough, I didn't have to change my rates as often
The Guide says that you can take the tax rates to 9% without anyone complaining - at first. Later it may be necessary to reduce them to 8%. % of what? I haven't found that in the Guide yet.
In this country we used to ascribe an historical value to the property and no we pretend that we are ascribing and up to date value. For a brief time we taxed on the number of people in the house and, to a limited extent, we still do that. But this is in addition to income tax, national insurance, sales tax (v.a.t.), etc., etc., etc.... Nobody 'challenges everything' - in fact few people challenge anything. I suppose that in a game it doesn't matter too much, but they don't challenge it even when it is for real.