What should I focus on when practicing my chosen scale and arpeggio?

Is my tempo steady?
Am I in tune as I go from one octave to the next?
Are my notes as in tune going down my scale/arpeggio as they were when I went up?

Tempo/rhythm: Use a metronome to help develop a steady tempo and accurate rhythm
Intonation: Use your tuner or an online tone generator such as the one at http://seventhstring.com/tuningfork/tuningfork.html) to produce the home tone of the scale or arpeggio you are practicing. If you have access to an iPod Touch, iPhone, iPad, or Android device to use while practicing, Tunable is a first rate tuning and tone generation app. Listen carefully as you play each note and adjust until you are in tune. This will help you develop a solid sense of tonality-based intonation
Listen to make sure that your pitches are the same going up and coming down (e.g. don’t be flat coming down your scale!)
Play with a consistent dynamic and articulation pattern