most Oscars i've had were bully's until they were put into place. Then they would be picked at until I ended up moving them or else ended up getting rid of them
There are always exceptions. I've had peaceful oscars, and I've had brutes......same goes for the texas. I think you just got an awsome list to choose from though! Good luck!
Petenia are normally peaceful as long they can't eat the tankmates, and they are a little more "different" than most of the common suggestions, although you can't go wrong with chocolates or severums.
I've got a spawning group/school of silver dollars (7) in with 3 Petenia splendida, 1 amphilophus amarillo (gets on great with the silver dollars just won't tolerate similar sized/shaped fish), and 1 crenicichla venezuala.
I've had them with Pearsei, and a small spot Polleni without any problems. It didn't work out with two Polleni, but that's another problem.
They did well with some datnioides, except the silver dollars tended to make the dats a bit skittish.
I also didn't have a problem with Hypselecara temporalis (chocolate cichlid) even when the chocolates layed eggs.