During my time in the college jazz band a few years ago, I came up with my own system of comping with 4-note chords. It served me well, but it was limiting when I couldn't think outside it to come up with different ideas. So I've been avoiding it in my chord studies until recently. I feel like I have a better knowledge of chords all over the neck now, so I'm going back to it again.

The system uses a few simple rules. I only use voicings on the top 4 or middle 4 strings. I substitute the 9 for the root on all chords (doesn't apply to m7b5 or dim7). The lowest note in the voicing can only be the 3 or 7 (doesn't apply to m7b5 or dim7). An expanded version allows the 5 in the bass, but those voicings are often difficult. When appropriate, I substitute the 13 for the 5 in dominant chords.

This gives me the following options, which can each be played on the top 4 or middle 4 strings, for a standard ii-V-I. Voices are listed low to high.

b3-b7-9-5 => b7-3-13-9 => 3-7-9-5
b7-b3-5-9 => 3-b7-9-13 => 7-3-5-9

The coolest part is b5 substitutions. The b7 becomes the 3 and the 3 becomes the b7, so they stay in the same spots. Then the 13 becomes the #9 and the 9 becomes the #5. Presto. You have an altered chord without moving a single note. The same exact fingering can be used for G13 and Db7#5#9 (Db7alt).