I think I can mentally process it faster than my fingers, but the scales are just..uneven and sloppy!
Technique, sigh.
If your scales are uneven and sloppy then you have a problem with timing and touch. First get yourself a metronome and become very good friends with it. One way to develop a good sense of time and also to speed up your scales is to start off very, very slowly. Try this exercise with the metronome set at, say 40 or 50 bpm.
(1) Play the C major scale, both hands, one octave apart, 4 octaves up and down at 4 BEATS per note. Yes, this is going to be painfully slow. Do it anyway and listen to each note, making sure each has the same volume.
(2) Repeat the scale, this time at 2 BEATS per note.
(3) Repeat the scale at 1 BEAT per note.
(4) Repeat the scale at 2 NOTES per beat.
(5) Repeat the scale at 3 NOTES per beat, 6 octaves up and down.
(6) Repeat the scale at 4 NOTES per beat, 4 octaves up and down.
(7) Repeat the scale at 5 NOTES per beat, 5 octaves up and down.
(

Repeat the scale at 6 NOTES per beat, 6 octaves up and down.
(9) Repeat the scale at 7 NOTES per beat, 4 octaves up and down.
Do this for each of your scales (perhaps one or two scales a day) and in a few weeks your scales will be fast and even.