To some extent, daggers are inefficient and are mainly only seen in the end of assassination talent builds and of course subtlety, pre BC they were used in combat dagger builds for raid DPS. None of this is important to you while you are wow powerleveling. You won't have enough talent points available to do anything beneficial with them so stick to combat primarily. It is important to learn to make use of health points, because health points are able to save lives and save corpse runs. But you should keep in mind that corpse runs take a lot of time away from wow powerleveling. More or less First Aid has many uses. You can gouge a mob and bandage or bandage after a fight. This is a very useful secondary profession for rogues to have.

 

By the same token, you must get food at your level. Don't by cheap stuff; you want to get the best food for your level that restores health as fast as possible. This one is obvious when you are fighting a mob make sure it has a "blue mana bar" under its health. Casters have a lot less hp and since you are a melee class it makes sense to just beat down caster mobs. You will kill more mobs and get more exp per hour. In the event you do have downtime you don't want to sit there the full 30 seconds eating if possible. It's bad enough some flights are 15 minutes you don't need to waste even more time eating.

 

As for a Rogue, Stamina and Agility are important for wow powerleveling. On the hand Stamina is your hit-points, on the other hand agility is your attack power, dodge, crit, and armor supplement. These are the only two stats you need as a Rogue. It is likely to say that everyone seems to save their evasion and blade furry (combat talent) for special occasions. Don't, use them to save on down time and kill faster whenever they are up unless you know they are absolutely needed in the near future. This goes for sprint to in the early level; it can help you travel around the world faster.