They need other things than accomplished feats in war....
Anakin was 9 when he begun his traning. Most or many jedi begun when they were months old.
Luke was still a padawan at the time, and he wasn't trained by an order of jedi, he was trained by Yoda and was the only hope for the future jedi. Anakin did also not evolve as quickly as Luke. (Might be that Luke was already old when he started his traning, thus he learnt faster, and had a less troublled past).
But this is very weird. People are differently powerful, thus you cannot say, "he is at the level of a master so he is a master", they don't have the same potential and skills. For example, Luke was awefully much above Yoda, still they were both grandmasters. Luke did not have a level of super jedi or force god, just a master for the time in NJO. Even if Anakin was better than any other padawan and possibly any knight doesn't mean he is a knight or should be one....