I've kept angels since the 80's and currently have 13 adults in a 220g with rummynose tetras, threadfin rainbowfish, a ton of cory's, oto's, rams, whiptail cats, loaches, and as of yesterday 6 Rachovii killifish. I also have about 50 shrimp and they don't pay them any attention. I imagine that lady didn't tell the full story. My guess would be if an angel truely attached some cory's is because the angel was an adult and established in the tank, and if it was a single, most likely had "the tank is mine syndrone", if she added some small new cory's without removing the angels and changing the tank then yep any fish would have have been a target. Plus she didn't tell you the size of the tank either. You have a large tank and if planted/decorated well with plenty of different areas and the line of sight being broken up from one end of the tank to the other there are all kinds of fish you could add and not have to worry.
With the stock you have a nice school of rummy nose or cardinal tetras would give a good splash of color. 6 angels would work fine even as mature adults. You could do 3-5
yo-yo loaches as they don't get overly big like clown loaches and tend to be alittle easier on liking to put holes in plants than other loaches. Kuhli loaches are very peaceful and different looking and you could have a nice number of them. Both loaches mix well with cory's. Plus a school of say rasbora's or diamond or lemon tetras would work nicely. Threadfin rainbow fish are beautiful, peaceful, and tend to stay in the upper water levels. Or you could do some of the other colorful peaceful rainbow fish. And look into Whiptail Cats or Twig catfish as they are also called for something very unique (I have 3 in my 220g). You have a ton of options all without worries of having your own horror fish story to tell.