When does your population growth hit 0? I did most of the things I said and I have my public order 80% or above. You don't really need to reduce your population if you can maintain 80% public order or above with it.

Example:
Let's say I have a city that can grow to 30,000 before growth becomes 0 at normal taxes. At 30,000, it will have a 100% penalty on public order. It has the maximum distance penalty from my capital (80%). Low taxes would increase population growth by 0.5% but increase public order by 30%, with a net of 25%. Juno would increase public order net by 50%. Arenas will increase it by 15% with yearly games. Curia will increase it by 10%. Having arena and hippodrome have monthly games and races each will add a total of 40%. You'll only need around 20% public order and you can have it with a garrison of around 8 peasant units.

So:

Squalor penalty = -100%
Distance penalty = -80%

I'll counter with:

Low taxes = net 25%
Juno = 50%
Arenas = 15%
Curia = 10%
Monthly games and races = 40%
8 peasant units as garrison = 20%

You'll have 80 public order at this point and no rebellions.