For me, I'd say a good husband is one that is ambitious, monogamous, well-educated, athletic, and has a sense of humor. Ambition is something that will propel him forward even through tough times, monogamy shows he can be trusted.
Well-educated people are likely to live longer and healthier lives because they understand how to take care of themselves and can tell the difference between fact and fiction in the realm of health. Not to mention that a well-educated person is better able to command a higher salary.
Athletic/active hubbies are much more likely to be around when you get older and they are more likely to be healthy, longer. A sense of humor is important for hubby and wife alike.