Symmetrical Tuning (warning, a little anecdotal)

I'm somewhat of a newb. I've been playing bass for only six months -- though it feels like it's been a year. Thing is, I've been messing with instruments for a few years now, but never sticking to any instrument: classical guitar, keyboard, flutes/whistles. The thing about music that most interested me was the theoretical side of things. Music notation is what I started to learn first before any instrument -- so my approach to all of this is a little different than the one that my guitarist friends tend to take.

One problem I've had with a couple of my friends is that I tend to ask questions they just can't answer -- like: "What makes this chord 'sustained'?", "Why do you use this pattern for a scale, and how did you come up by it?" You can see that many of my friends learned by chord/scale chart, tab, and memorization. The big question I had, and this is the subject of this post, was: "Why are the strings arranged EADGBE?" Of course, most of the guitarists I know believe that this tuning is the best one. One of my eclectic friends wanted to toy with open chord tunings. What bothered me was that standard tuning was not symmetrical, and because of which, threw me off when playing scales. It seemed arbitrary. Looking at different tuning systems now, it would seem that the major 3rds tuning and perfect fourths tunings are promising tries. My experiments with guitars at different shops and different people's houses has left me under the impression that perfect fourths might be worth a shot.

So, my questions for all of you are: what are the flaws in the perfect fourths and major thirds tunings, and what are the perks?

Originally Posted by: apoth why do you use this pattern for a scale, and how did you come up by it?". The big question I had, and this is the subject of this post, was: "Why are the strings arranged EADGBE?"
So, my questions for all of you are: what are the flaws in the perfect fourths and major thirds tunings, and what are the perks?

why do you use this pattern for a scale

The answer to that question is simple.
Is about the fingering that allows you to play the notes of that scale without having to stretch your finger more than five frets. Which makes things easier when "sweeping" that scale.

"Why are the strings arranged EADGBE?"

The basic musical scale unit of ancient Greece was the tetrachord meaning literally four strings.The notes of the tetrachord were always tuned to the interval of a diatessaron (fourth)

If you've got some extra spending money, I'd suggest buying Fretboard Logic. The author goes into detail about why the guitar has the unusual tuning system that it does. I'll reread that part when I get home from work and post a synopsis, but IIRC, it's so that playing chords would be possible.