There are two main ways to structure a cause & effect essay. These are similar to the ways to structure problem-solution essays , namely using a block or a chain structure. For the block structure, all of the causes are listed first, and all of the effects are listed afterwards. For the chain structure, each cause is followed immediately by the effect. Usually that effect will then be the cause of the next effect, which is why this structure is called 'chain'. Both types of structure have their merits. The former is generally clearer, especially for shorter essays, while the latter ensures that any effects you present relate directly to the causes you have given.
Although this sentence has a contrast transition , the criteria for contrasting are not the same. The criteria used for Aaron are height (tall) and strength (strong). We would expect similar criteria to be used for Bruce (maybe he is short and weak), but instead we have new criteria, namely appearance (handsome) and intelligence (intelligent). This is a common mistake for students when writing this type of paragraph or essay. Compare the following, which has much clearer criteria (contrast structure words shown in bold).