I'm hooker for my high-school varsity rugby team, and I'm 6'2" and 225 lbs. Our last hooker was 5'11" and 215 lbs. I suppose its more skill than size (don't get me wrong size helps) It's also about weight distribution, center of gravity etc. As long as your Props are the same size, you should be good during the scrum.
well hookers whom are shorter normally are better but I know people whom are almost 6ft tall and are very good at it
the hooker on my high school aaa team was 5'1 and about 150 pounds but we arnt a very big team I play flank and im 5'2 and 120 pounds our biggest player is about 5'10 and the heaviest mabey about 180 pounds
shorter the better for a hooker, puts extra strain on the opposition front row and cause them to collapse the scrum giving away a penalty
Usually hookers are known to be around 6 ft (1.83 mts) and around 105 kg.