Is a man who has never committed a sin in his life considered better than a man who has both good deeds and misdeeds, or is the balance between good deeds and misdeeds the criterion, such that the one whose good deeds are more numerous is better?

The superiority of people in the Hereafter cannot be asserted except with a legitimate Shar'i proof. And indeed, one who distinguishes himself with virtuous deeds (such as jihad, knowledge, frequent recitation of the Quran and remembrance of Allah, and charity) may surpass others, and his evil deeds may be outweighed by his good deeds. Sheikh Al-Islam Ibn Taymiyyah was asked about which is better: a reciter of the Quran who does not act upon it, or a worshipper? He replied: "If the worshipper worships without knowledge, he may be worse than the sinful scholar, and the sinful scholar may be worse than him. If he worships Allah with knowledge and fulfills obligations and abandons prohibitions, then he is better than the sinful person, unless the sinful scholar has good deeds that outweigh his evil deeds, such that he has more good deeds remaining from them than the good deeds of that worshipper."