Yeah, he shouldn't have spoken out against condoms in Uganda -- but the idea of someone in his position preaching anything other than straight monogamy is completely unrealistic. I would, you would -- but we ain't about to become pope.
As for Arinze, he sounds quite a bit like John-Paul II, actually: good on political issues (sharing wealth, reconciliation between different religions, etc.) but deeply conservative on issues of sexual morality and the place of women. (And not about to shut down Opus Dei either.)
An article in
The Guardian on him from a year and a half ago quotes this description of the man: "He is a popular fellow. He makes you laugh, he doesn't stand on ceremony, he answers his own phone, and he's comfortable with women."