Not sure why it would be a weird looking combo. They all live to in the wild, but everyone can have their opinion. BTW on that stocklist the discus would be the least expensive by far.
I think what I would try to do is stock it with rays, arrowana, and discus. Let those fish settle in for a while. Then in a morning introduce 1 pike and watch it all day. If things go well for like a week then introduce the other 2 to 3 pikes and again observe them all day. Once all that is in place try the same thing with a peacock bass.