All severums have different personalities, just like chocolates do. My chocolate cichlid is moody and shy. She's all bark and no bite. She sometimes flares up at tank mates, but the second they push back, she backs down into her little pit under some driftwood.
I have about 12 severums in the tank and they range from friendly and peaceful to aggressive and pushy. It's really all in the individual fish.
Golds are usually a more buttery yellow color while "super reds" are the more fiery orange-red color. Golds start out looking pretty pale as juvies but most turn more yellow/golden as they grow. Males will develop red lines on the face and body. Nothing beats a good quality gold, IMO. I've always had a soft spot for them.
What size tank are you upgrading to? Chocolates and sevs get pretty big. I wouldn't try anything less than a 90 or a 125, depending on how many other fish you put with them.