Not sure why your anemones would need to be protected from a dwarf angelfish
Ourdwarf angels have never had any interest at all in anemones. I am guessing a large clown could fend them off if need be but probably not a smaller clown fish. Pretty much any dwarf could fit in a 60 gallon tank as long as you have enough live rock for them. Over the years I have had several, and my favorite is the Flame and lemonpeel but they are all are beautiful and a matter of personal choice. I think the couple of coral beauties we have had have the least interest in people. They have not been afraid of us, but couldn't care less about interacting. My flame loves attention.