None of the cichlids you have chosen are known for their placid nature.
Jewell cichlids for their size are very aggressive. Every texas cichlid I have owned has grown up to be very aggressive.
In my experience JDs can be a bit more laid back but aggression will vary between individuals and some are down right nasty.
Your tank although not a bad size,is just too small for the fish you re choosing to live together.
Severums can be a bit easier going but get to a big size.
If you like Severums,have you looked at rotkiels they are very attractive and a little smaller.
You could have a pair with some nice catfish and medium sized tetras.
It would be an interesting tank and a lot less hassle.It would also be kinder on the fish.