My female is extremely territorial but not aggressive. she has never attacked another fish. with these fish its all about show. the large males though will definately show their aggressive nature. I'm not sure why people don't bring this up anymore maybe it was incorrect, but I'm sure I read in many books that the salvini is a guapote. like Jaguar, mota and other parachromis. it certainly looks like a miniature parachromis. and has the yellow female vs more drab male colouration.
either way do not underestimate them. if you want a peaceful one try for a female. they have black in their dorsal fin and more colour. males will be drab with clear dorsal fins. My female can stand upto bigger fish like my syn but she also leaves the smaller fish alone. I have 8 columbian tetras (all about 5 years old and quite big) a few black skirts (these are all dithers) and then I have some less aggressive species like geophagus steindachneri. the salvini leaves all of them alone, providing they stay out of her territory.
So with the stocking you have I see no reason why it can't work if you get yourself a female. your tank is very long and for fish this size you have enough room to make lots of territories so I honestly think you should be fine.
also can I add, if you chose to get more than one female you will have a matriarch. I got 2 small females, one grew faster and larger coloured up amazingly, the other one is more drab with no fin extensions. if you get multiple females they will work out a pecking order and you will have one really pretty matriarch and a few smaller less colourful ones.