Thiam is currently CEO of Prudential, a multinational life insurance and financial services firm headquartered in London. He speaks English, French and German and was born in the Ivory Coast, but educated in France.
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Dougan said Thiam had done a "brilliant job" of growing Prudential's business in emerging markets, particularly in Asia-Pacific.
"We have worked together for a number of years and I have a lot of admiration for him," Dougan told CNBC.
"He is a very smart guy. I think he has got courage; I think he has got good vision."
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Swiss banks have come under pressure following criminal investigations by the U.S. and other countries into allegations that they have provided tax shelters for international clients. Last year, Credit Suisse pleaded guilty to helping Americans evade taxes and paid a fine of around $2.5 billion to U.S. authorities.
The heat then rose further for the bank in January this year, when the Swiss franc surged after Switzerland's central bank removed its three-year-long currency cap against the euro.
Dougan said the impact of the appreciation in the Swiss franc was "very manageable," but conceded that settling with the U.S. had proved "tough."
"I like the fact that we have got a lot of the legacy issues behind, and in terms of the more recent issues, we have avoided a number of things, like (the) Libor and FX (scandals) et cetera. I think certainly some of the issues were difficult to get through. Certainly, the cross-border settlement with the U.S. was a tough issue to work through; I think we did the best we could with it, but it was a tough issue," he told CNBC.
The 55-year-old hinted that his future plans might not involve banking.
"Being the CEO of a global bank, eight years is a long time to be doing that, so I don't know if I would immediately jump back into something like that, even if I had the opportunity," he said.
"But I think there are probably other things that are pretty interesting. There are a lot of things that are quite interesting to me, so we will see."