cleverstuff

this isn't really about metal but I figured this is the best place to go to find the most knowledge for what I seek. I'm looking for better and more information on chords in a diatonic scale. ive found different variations of this but I was hoping to find a better answer seeing as how every key isn't exactly the same and they can vary to show or excentuate different sounds in a major or minor chord one variation of a scale I found is a G major I g, g6, gmajor7,g6/9,gmajor9 ii Am, Am7, Am9, Am11, Am13 iii Bm, Bm7, Bm7add11 IV C, C6, Cmajor7, C6/9, Cmajor9, C6/9#11, Cmajor9#11 V D, D7, D9, D9(13) vi Em, Em7, Em9, Em11 vii F# half diminished, F#m11flat5, F#m11flat5flat13 ive found a even more drawn out version but I'm not about to type it all. so my biggest question starts at is there some sort of equation I can use to figure out which chords to use for a more general overall sound. my next question Is about octaves and its a matter of is there an equation to find the mean or somthing of that nature of the note frequencies of a chord to find which chord will better fit into the octave group that you are trying to chromaticly make like I wouldn't want to play a ton of open chords and pretend all bar chords are the same and play a barred g major and act like it fits. that's all I can think of at the moment but I have a few others so if they pop in and you guys are a bunch of know it alls as all metal guys should be then ill hit you with those too. thanks for the vast knowledge in advance.