I was doing a similar research an year ago.

Cheapest EU country just for Profit Taxes is Bulgaria. There you are paying just 10% as taxes. But still the money remain company's money. If you want it clean for you, you need to pay 5%-15% dividend taxes. In Bulogaria you need to pay and monthly ~80 social taxes.  It's mandatory.

Another good options are Malta and Croatia. For example in Croatia you could have a company and you are not obligated to pay yourself a salary (taxes respectfully).