You've already gotten some good advice, but here's my current experience with a few of the fish you've discussed.
I've got a black angel and rotkeil in my 75. They were young when I put them in last November and are now both about 4" long. The rotkeil has been a perfect citizen in the tank for the past 7-8 months. It never bothers my tetras and only gives a quick chase to keep the angel out of its very small territory in the back of the aquarium.
The angel on the other hand is a complete butthead with everything in the tank including the rotkeil. It tried to kill another angel immediately after my wife put the new angel in the tank, and it wants nothing within a foot of it when it's eating. We put a small electric blue acara in with them about 4 months ago. It's growing like a weed, but like the rotkeil is completely non-aggressive for now. And yeah the angel chases the acara away as well. What a miserable creature. Great fish though. I call them the 3 Stooges. They're all very interactive with people.
As I've quickly learned after starting my aquariums about a year ago, it all depends on the particular fish, especially when it comes to cichlids. My 125 is just as weird as the 75, but with the exception of the angel drama all I've seen is chasing and no serious attacks.