Only reason to get another Les Paul is as a backup if you're playing live and it's like your signature guitar, or you want to have totally different setups/pickups etc and just want to keep the familiar Les Paul.
I'd look into another body style if you want to stick with Gibson, such as an SG. At least try some out, they're pretty sweet. Otherwise you can't go wrong with a Telecaster or Stratocaster, it will open up a whole new world of sounds. They are very different (in terms of feel) to play though.