I think you would be alright with a sal gt and 2 male cons for a good amount of time.. Sals can be a very fiesty cichlid, but if your not planning on having a pair of them they usually just defend themselves and chase others out of their territory - never really heard of them being overly aggressive.. I think by getting them all at juvies, it will work better..
I have a male salvini with a various cichlids and it's actually quite peaceful. I'd say you could go towards a severum, firemouth, or JD if you want something more peaceful than cons; or you could go with jewel cichlids if you're itching for something mean.
A midas cichlid might work too although I have no experience with them.
I have a Salvini in with an Oscar, JD, and some SD's and there is no problems. They are all pretty big as well, The Salv used to be in with a GT and I had to remove her, she wasnt the problem it was the GT.