As i can read in your brief, you are loogin for big and wealthy clients. so you need an international logo, there submits power and elegance. my guess is that you will get a lot of sun logo's from your conuntrymen.
But please note that it is as you wote international clientel you are trying to attaract.
i have tried to combine these qualityes. and i think that i have made a trustworthy logo there is easy to remember and give a positiv attitude to any advertisment. becouse of the advertising psycology of the colors.