HTH - yeah, I hear you. Currently I play by ear with the songs, come up with some nice ideas. But I've always been intrigued by guitarists who take a more compositional approach - e.g. Frank Zappa. If there are more possibilities out there, I think it's always worth learning them. Playing by ear can be natural and open up lots of ideas but it can also restrict you to the only possibilities your musical ear already knows IMO.
Kilby - will definitely take a look at that! Thanks for that! Because we are definitely not a metal band, and I don't even really like metal - XTC are a cool band!
FWIW, I'm not trying to sound different tonally, I'm looking at harmony. And all the obvious stuff is already covered, so I'm gonna take a good look at this XTC stuff.