I would say 2001 for Barry Bonds. He hit 73 homeruns (a new record for a season), he had a 515 on base percentage and broke the all time slugging percentage record ever. Another one would be Barry Bonds 2004 season. He broke the all time intentional walks record with 120 and had 232 total walks. He had a 362 batting average and a 609 on base percentage. 609 OBP!!! He also hit 45 homeruns that season.
What hitting seasons could be more dominate?