I'm pronouncing it TASS-ih-lo in my head, and I like it. Of your combos, I like Tassilo Simon, Tassilo Peter, and Tassilo Marcus best.
*****
And last of all an Admiral came,
A terrible man with a terrible name,—
A name which you all know by sight very well;
But which no one can speak, and no one can spell.
Robert Southey, "The March to Moscow"