To me, just practicing up and down scales as a technical exercise has limited usefulness. I prefer to practice scale patterns that I can use in jazz improvisation and it trains my ears while having the side effect of improving technique. Getting acquainted with the 5 positions of major/minor diatonic scales is a good first step to knowing the notes on the fingerboard. Knowing those and then being able to stitch them together for 3-note per string and 4-note-per-string scales is useful. It will help with your a,m,i scales. I'm not a fan of the Segovia scales but they can't hurt. Once you know all that, you've basically practiced playing 2nds across the neck in a diatonic key, helping to know and hear where the major/minor seconds are. Then do 3rds, 4ths, 5ths, 6ths, 7ths, octaves, 10ths. This helps you know where in the 4ths, for instance, the augmented 4th is and where in the 5ths the diminished 5th is--all very useful in jazz improv. Also being able to play the triads 1-3-5, 2-4-6, 3-5-7, etc. within the scale is useful. To me, this may not be simply playing up and down scales in 2nds like Segovia recommends, but it helps you really know the scales and corresponding intervals and chords that are built from the scales which is more useful for understand, playing, and composing music. So you're accomplishing multiple tasks instead of just doing finger gymnastics.
An eyewitness will often only see what he already believes to be true.