I wouldn’t mind if Hook was older than Rumple, however i just can’t see it due to the actors, Colin is only 31 while Robert is 48, and no makeup can really cover that up.
Indeed, but the theory that Hook is older relies on him having been to Neverland before, (which people are wondering about, because he seemed very certain in his knowledge of the place when he told Smee that’s where they were going). There’s every chance that he could have lived in Neverland for 100 years as a child, and only aged to adulthood after he left.