I found a very interesting link. You can compare your income tax for 4 different situations (single, married, married with two children and after pension age - unfortunately other situations are missing) with different incomes. Also wealth tax is not considered, so only use it for a first overview.
Where is your tax paradise (German).
I can recommend Zug Canton and especially Baar commune. Before my son was born I paid 4.5%. Now I pay 2.5% minus 300 of family allowance, which in practice means that the tax authorities pay me taxes. If you have two kids the tax burden goes to 1.5%. There some other factors to take into account - for instance if you’re married, if both of you are employed, if you’re taxed at source etc. You can expect however in worst case about 5% of income tax.