Ah, ok, so 19% then.
If you create a company in Greece you will pay 22% CIT plus the 5% in
dividends, same procedure as you were describing in your initial post for the
UK LTd.
You can also pay yourself from the company as a freelance (or a director) up to 30K+ to benefit from the lower tax rates that you show and get the rest as dividends from the company. All completely legal. Do the math, the breakeven will probably be above 30K. You'll have to take into account other levies and costs (Social Security, company setup and maintenance, etc) that I am not familiar with.
Leaving it outside of the country will likely give you more trouble, I guess. At least if you bring it back and declare it as dividends they cannot say you were hiding it.
What do you think about an LLP in the UK (also tax transparent there)?